A full Aimosti report, start to finish

This is the real Aimosti report engine rendered over a made-up genome. This report is deliberately loaded with findings so you can see everything we check. Most real reports are much quieter, which is great news.

This is the report you get — a re-analysis of the DNA file you already own, from €79 (chip) or €119 (whole-genome). Yours to keep, updated as the science moves.

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Whole-genome (WGS) Chip upload (23andMe / Ancestry)

A chip array reads a fixed set of common spots; whole-genome sequencing reads (nearly) the entire genome. Both make a real, complete report — flip between them to see exactly what each file unlocks. A chip already powers pharmacogenomics, polygenic scores, traits, ancestry and the common single-gene findings; whole-genome data adds the rare-variant clinical & carrier panels and Deep Read.

Your re-analysis report

Reference build GRCh38 · generated 2026-07-23

Counts only, never a verdict. Open each finding for the detail. An empty section means "not found in the regions examined", never "examined and clear".

Your genotyping chip, read in full. A complete report over everything an array genuinely calls — your pharmacogenomics, polygenic risk scores, traits, ancestry, and well-characterised single-gene findings (APOE, HFE, Lp(a), ABO). It's a real report, and it's yours to keep. A genotyping chip reads only a few hundred thousand pre-selected positions, about 0.02% of your genome, chosen for common variation. It does not sequence the rest, so it cannot find the rare or novel pathogenic variants the clinical and carrier modules look for: a “no finding” from chip data means “this chip never looked”, far more so than with whole-genome sequencing. Chip data suits common-variant traits, pharmacogenomic tag SNPs, and haplogroup ancestry, not clinical or carrier screening. The rare-variant clinical & carrier panels and the read-level Deep Read panel need a whole-genome (WGS) or aligned-reads file — a later upgrade whenever you want it, never a correction. Nothing here is missing for what a chip can do.

Tier 1 · Established

Clinical findings: single variants only

A genotyping chip can reliably read a small set of single-variant findings, but not the full clinical-findings panel or carrier status (those need whole-genome data). From your chip we checked these specific variants: Factor V Leiden thrombophilia, Prothrombin G20210A thrombophilia. Any detected below are shown as single-variant findings: for that variant only, never a diagnosis. Upload a whole-genome (WGS) file for the full clinical and carrier panels.

Risk factors

Common, well-established variants that modestly shift risk: context to be aware of, never a diagnosis.

F2 Prothrombin G20210A thrombophilia ☆☆☆☆Low: a modest risk factor Discuss with a clinician

Prothrombin G20210A is a common, well-established variant that modestly raises the chance of abnormal blood clots. Like Factor V Leiden, it is a risk factor, not a disease or a diagnosis.

Evidence ☆☆☆☆ Effect Low: a modest risk factor

Variant: 11:46739505 G>A · rs1799963
Your genotype: heterozygous
ClinVar classification: Established common risk factor
ClinVar’s reported condition: Prothrombin G20210A thrombophilia
Confidence: ☆☆☆☆ curated single-variant finding
Population frequency: frequency unknown
Inheritance: Autosomal dominant (risk factor)

Prothrombin (clotting factor II, the F2 gene) is one of the proteins that lets blood clot. The G20210A variant (rs1799963) sits in a non-coding part of the gene and slightly increases how much prothrombin the body makes. A little more prothrombin means blood clots somewhat more readily than average.

This is a modest risk factor, not a diagnosis. It is one of the two most common inherited clotting variants in people of European ancestry (the other being Factor V Leiden), and the large majority of people who carry one copy never have a clotting problem. As with Factor V Leiden, the variant matters most in situations where the baseline clot risk is already raised: pregnancy, surgery, prolonged immobility, or oestrogen-containing contraception.

Carrying two copies, or carrying it alongside Factor V Leiden or other clotting risk factors, increases the effect further. The fair framing is "a common risk factor worth being aware of", not alarm.

This is a common risk factor, not a clinical diagnosis. If you have a personal or family history of blood clots, discuss it (and this finding) with a doctor before any decision (for example about contraception or clot prevention).

Sources: MedlinePlus Genetics: F2 gene · MedlinePlus Genetics: Prothrombin thrombophilia

F5 Factor V Leiden thrombophilia ☆☆☆☆Low: a modest risk factor Discuss with a clinician

Factor V Leiden is a common, well-established variant that modestly raises the chance of abnormal blood clots. It is a risk factor, not a disease or a diagnosis.

Evidence ☆☆☆☆ Effect Low: a modest risk factor

Variant: 1:169549811 C>T · rs6025
Your genotype: heterozygous
ClinVar classification: Established common risk factor
ClinVar’s reported condition: Factor V Leiden thrombophilia
Confidence: ☆☆☆☆ curated single-variant finding
Population frequency: frequency unknown
Inheritance: Autosomal dominant (risk factor)

Factor V Leiden (the F5 rs6025 variant) is one of the most common inherited variants affecting blood clotting in people of European ancestry. Normally a protein called activated protein C switches off clotting factor V at the right moment; the Leiden variant makes factor V slightly resistant to being switched off, so blood clots a little more readily than average.

This is a modest risk factor, not a diagnosis. Most people who carry one copy never have a clotting problem. The variant becomes more relevant in specific situations: during pregnancy, after surgery, with prolonged immobility, or alongside oestrogen-containing contraception, where the baseline clot risk is already raised.

Carrying two copies, or carrying it together with other clotting risk factors, increases the effect further. This is exactly the kind of common, well-replicated finding where the the fair framing is "a common risk factor worth being aware of", not alarm.

This is a common risk factor, not a clinical diagnosis. If you have a personal or family history of blood clots, discuss it (and this finding) with a doctor.

Sources: MedlinePlus Genetics: F5 gene · MedlinePlus Genetics: Factor V Leiden thrombophilia

APOE: Alzheimer’s-risk genetics

Sensitive · opt-in

Read this before you reveal it. APOE is the strongest common genetic influence on the risk of late-onset Alzheimer's disease. Your two ε alleles place you in a relative-risk band: higher or lower than the average ε3/ε3 genotype. It is one factor among many, it is not a diagnosis or a forecast, and nothing you can do changes the gene itself. APOE is a risk factor, not a diagnosis and not a prediction. Most people who carry an ε4 allele never develop Alzheimer's disease, and many people who develop it carry none. No treatment changes your APOE genotype, and clinical guidelines do not recommend APOE genotyping to predict dementia in people without symptoms. We show it because it is your information (which some people value for life, family and financial planning), not because it tells you what will happen.

Reveal my APOE result

APOE ε3/ε4 Increased

One ε4 allele: increased relative risk for late-onset Alzheimer's.

Your genotype: ε3/ε4
Relative risk vs ε3/ε3: Above ε3/ε3: roughly 2–3× with a single ε4 copy.

A single ε4 copy raises late-onset Alzheimer's risk relative to ε3/ε3, commonly cited around two- to three-fold in European-ancestry studies. This is the most common ε4-carrying genotype. Carrying ε4 is far from a diagnosis (the majority of single-ε4 carriers never develop Alzheimer's), but it does move you into a higher band, and the effect tends to be larger in women.

How to read this: ancestry, sex & the limits of the number

The size of the ε4 effect depends on genetic ancestry and sex. It is strongest in people of East Asian and European ancestry and substantially weaker in people of African ancestry; the relativities shown here come mostly from European-ancestry studies. Women who carry ε4 appear to be at somewhat higher risk than men, particularly with a single ε4 copy. Read every number as a broad population average, not your personal odds.

What this isn’t: APOE is a risk factor, not a diagnosis and not a prediction. Most people who carry an ε4 allele never develop Alzheimer's disease, and many people who develop it carry none. No treatment changes your APOE genotype, and clinical guidelines do not recommend APOE genotyping to predict dementia in people without symptoms. We show it because it is your information (which some people value for life, family and financial planning), not because it tells you what will happen.

Only one of the two ε-defining markers was covered in your file — rs7412 was not found. The ε-diplotype is read from rs429358 and rs7412 together, so the unobserved marker is assumed reference here. A variant file can’t prove that position was actually covered, and if rs7412 carried a variant your diplotype — including your ε4 (Alzheimer’s-risk) status — could differ. Treat this as a provisional call; a whole-genome or gVCF file covering both markers can confirm it.

2026-06-03 · MedlinePlus Genetics: APOE gene · NIA: Alzheimer's Disease Genetics Fact Sheet · Farrer et al. 1997, JAMA: APOE and Alzheimer risk meta-analysis (PubMed) · dbSNP: rs429358 · dbSNP: rs7412

Lipoprotein(a): inherited heart-risk marker

Lipoprotein(a), or Lp(a), is a largely inherited, independent and causal risk factor for heart disease and aortic valve narrowing. Your level is mostly fixed for life. We can read two common genetic markers that flag a high level, but they are a partial proxy, not a measurement.

LPALp(a)Likely elevated

A marker linked to elevated Lp(a) is present.

What this reads as: One tag allele: associated, on average, with a higher Lp(a) level and higher cardiovascular risk.
Markers found: rs10455872 (heterozygous)

You carry one copy of a tag allele associated with elevated lipoprotein(a). On average this points to a higher-than-typical Lp(a) and a modestly higher risk of heart disease and aortic stenosis, but the effect size varies widely between people, because the tag is only a partial stand-in for the actual level. Confirm with a blood test before drawing any conclusion.

How to read this: ancestry & why a blood test is the real answer

The two tag markers we can read were characterised mainly in people of European ancestry and capture only part of the genetic signal in other groups. A negative read is therefore even less informative outside European ancestry. Genetic ancestry never substitutes for the blood test.

Important: This is a genetic proxy, not a measurement. The main driver of Lp(a), the LPA KIV-2 repeat, cannot be read from a variant file, so these markers can flag a likely-high level but can NEVER rule one out. The only way to know your Lp(a) is a one-time blood test (reported in nmol/L); guidelines suggest measuring it once in adulthood. Discuss results and any treatment with a clinician. Lp(a) is not changed by diet, and targeted Lp(a)-lowering drugs are still in trials.

2026-06-03 · MedlinePlus Genetics: LPA gene · Clarke et al. 2009, NEJM: LPA variants (rs10455872, rs3798220) and coronary disease (PubMed) · dbSNP: rs10455872 · dbSNP: rs3798220

APOL1: inherited kidney-disease risk

APOL1 risk variants are the strongest common genetic influence on several kidney diseases. They are found almost entirely on West/Central African ancestral haplotypes, where they likely persist because they protect against African sleeping sickness. Two risk alleles raise kidney-disease risk. It is a risk factor, not a diagnosis, and an actionable one.

APOL1G0/G0Typical risk

No APOL1 risk allele: typical risk.

Relative risk: Reference: typical APOL1-related kidney risk.
Risk alleles found: 0 of 2

You carry no G1 or G2 risk allele, so APOL1 does not raise your kidney-disease risk. This is the expected result for most people, and universally so outside West/Central African genetic ancestry.

How to read this: ancestry & the limits of the number

The G1 and G2 risk alleles arose on, and are essentially confined to, West/Central African genetic ancestry. Ancestry is not race, and allele frequencies vary continuously across people. This finding applies to anyone who carries the alleles, however they identify. Outside that ancestry the alleles are vanishingly rare, so a 'no risk allele' result is expected there and tells you little.

Important: Two APOL1 risk alleles raise the risk of chronic kidney disease and FSGS, especially alongside a 'second hit' such as HIV or certain infections, but most people with the high-risk genotype never develop kidney failure. This is actionable in a good way: clinicians manage APOL1 high-risk status with blood-pressure control, avoidance of kidney-toxic drugs, and kidney-function monitoring, and APOL1-targeted treatments are emerging. Discuss with a clinician; this is not a diagnosis.

No APOL1 risk marker was found in your file, so this reads as no risk allele, the expected result, and universally so outside West/Central African ancestry. A variant file can't prove those positions were covered, so treat this as an inference.

2026-06-07 · MedlinePlus Genetics: APOL1 gene

Hemochromatosis (HFE): inherited iron-overload risk

Hereditary haemochromatosis is a condition in which the body can absorb and store too much iron over many years. It is strongly linked to two common changes in the HFE gene. Carrying an at-risk combination raises the chance of iron overload, but most people who carry one never develop a problem, which is why this is a risk factor, not a diagnosis.

HFEno risk allelesNo risk alleles

Neither HFE risk change was found.

What this reads as: Neither HFE risk change was found: the common genotype for this gene.
Risk alleles found: None of the two HFE risk changes

Neither the C282Y nor the H63D change was found in your file, which is the common result. This makes hereditary haemochromatosis from these two well-known HFE variants unlikely. It does not rule out every rarer cause of iron overload, and, because a variant file cannot prove a position was covered, it is best read as 'not flagged', not a guarantee.

How to read this: penetrance & why a blood test is the real answer

Penetrance is low and very variable: many people with even the highest-risk genotype (two copies of C282Y) never develop iron overload, and it is less common and usually milder in women, who lose iron through menstruation and pregnancy. Genetics set the predisposition; whether iron actually accumulates depends on age, sex, diet, blood loss and other factors.

Important: This is a genetic risk factor, not a diagnosis and not a measurement of your iron levels. The only way to know your iron status is a simple blood test, ferritin and transferrin saturation, which your clinician can interpret. Hereditary haemochromatosis is very treatable when caught (usually by periodic blood removal), so an at-risk genotype is information to act on calmly with a clinician, never a cause for alarm.

Neither HFE variant was found in your file, so this reads as the common no-risk-allele genotype. A variant file can't prove those positions were covered, so treat this as an inference rather than a confirmed negative.

2026-06-04 · MedlinePlus Genetics: HFE gene · GeneReviews: HFE Hemochromatosis (Porto et al.) · dbSNP: rs1800562 (C282Y) · dbSNP: rs1799945 (H63D)

Tier 2 · Well-supported

Pharmacogenomics

2 actionable

How your genotype may affect specific medicines, restating CPIC guideline guidance for gene–drug pairs callable from your file. Information to discuss with a prescriber, never an instruction from us. Some pairs are out of scope for a standard variant file (e.g. CYP2D6 and TPMT’s common *3A) and are deliberately omitted rather than guessed. CYP2D6 can be resolved from your aligned reads: see Deep Read.

SLCO1B1 *1/*5 Decreased function

A liver transporter that pulls statins out of the blood. Reduced-function variants raise statin exposure and the risk of muscle side-effects.

Your alleles: *1 (Normal function) · *5 (Decreased function)

One decreased-function (*5) allele raises blood statin levels.

Simvastatin

Higher exposure and a moderately increased myopathy risk, dose-dependent.

CPIC: the guideline suggests a lower simvastatin dose or an alternative statin (e.g. one less dependent on SLCO1B1), with routine creatine-kinase awareness.

Every defining variant for this gene was on your array: this call is read directly, not assumed.

Which defining variants were on your array (1)

rs4149056 (*5): on your array (T/C)

CPIC CPIC (statins 2022) · CPIC: statins & SLCO1B1 (and others)

VKORC1 A/A Highly increased sensitivity

The vitamin-K-epoxide-reductase gene warfarin acts on. A common promoter variant (-1639A) lowers its expression and raises warfarin sensitivity.

Your alleles: A (Reduced expression) · A (Reduced expression)

Two -1639A alleles markedly lower VKORC1 expression and raise warfarin sensitivity.

Warfarin

Markedly greater sensitivity; a notably lower dose is often required.

CPIC: warfarin dosing follows the genotype-guided algorithm; two -1639A alleles predict a markedly lower dose and closer INR monitoring.

Every defining variant for this gene was on your array: this call is read directly, not assumed.

Which defining variants were on your array (1)

rs9923231 (A): on your array (A/A)

CPIC CPIC (warfarin 2017) · CPIC: warfarin, CYP2C9 & VKORC1

Could not be resolved from your file (6)

We don’t assign a result where the data can’t support one: see each gene’s note.

CYP2C19 CYP2C19

A liver enzyme that activates clopidogrel and clears several antidepressants and acid-blockers. Common variants raise or lower its activity.

Your array typed some but not all of this gene's defining variants, so we can't resolve the full diplotype (not on your array: *3, *17). See the per-variant breakdown below.

Which defining variants were on your array (3)

rs4244285 (*2): on your array (G/A)
rs4986893 (*3): not on your array
rs12248560 (*17): not on your array

CPIC CPIC (clopidogrel 2022; SSRIs 2023) · CPIC: clopidogrel & CYP2C19 · CPIC: SSRIs & CYP2C19/CYP2D6

CYP2C9 CYP2C9

A liver enzyme that clears warfarin, several NSAIDs and phenytoin. Reduced-function variants slow that clearance.

The defining variants for this gene aren't on your array (*2, *3), so we can't call it from chip data: this is "not examined", never a reference result.

Which defining variants were on your array (2)

rs1799853 (*2): not on your array
rs1057910 (*3): not on your array

CPIC CPIC (warfarin 2017) · CPIC: warfarin, CYP2C9 & VKORC1

CYP4F2 CYP4F2

An enzyme in vitamin-K recycling. The *3 variant lowers its activity, which slightly raises the warfarin dose people tend to need.

The defining variants for this gene aren't on your array (*3), so we can't call it from chip data: this is "not examined", never a reference result.

Which defining variants were on your array (1)

rs2108622 (*3): not on your array

CPIC CPIC (warfarin 2017) · CPIC: warfarin, CYP2C9, VKORC1 & CYP4F2

DPYD DPYD

The enzyme that breaks down the chemotherapy drugs 5-fluorouracil and capecitabine. Reduced-function variants can cause severe, occasionally fatal toxicity at standard doses.

The defining variants for this gene aren't on your array (c.1905+1G>A, c.2846A>T), so we can't call it from chip data: this is "not examined", never a reference result.

Which defining variants were on your array (2)

rs3918290 (c.1905+1G>A): not on your array
rs67376798 (c.2846A>T): not on your array

CPIC CPIC (fluoropyrimidines 2017) · CPIC: fluoropyrimidines & DPYD

HLA-B HLA-B

An immune-system variant that sharply raises the risk of severe, sometimes fatal skin reactions (Stevens-Johnson syndrome / toxic epidermal necrolysis) to the seizure and nerve-pain drug carbamazepine and its relatives. It is most common in people of South-East and East-Asian genetic ancestry, where the FDA recommends testing before carbamazepine; ancestry is not race and the variant is read via a strongly-linked tag marker, so a negative result is not a global exclusion.

The defining variants for this gene aren't on your array (*15:02), so we can't call it from chip data: this is "not examined", never a reference result.

Which defining variants were on your array (1)

rs144012689 (*15:02): not on your array

CPIC CPIC (carbamazepine/oxcarbazepine & HLA-B 2017) · CPIC: carbamazepine/oxcarbazepine & HLA-B

NUDT15 NUDT15

An enzyme that detoxifies thiopurine drugs (azathioprine, mercaptopurine). Reduced-function variants raise the risk of severe bone-marrow suppression, and are most common in East-Asian and Hispanic ancestries.

The defining variants for this gene aren't on your array (*3), so we can't call it from chip data: this is "not examined", never a reference result.

Which defining variants were on your array (1)

rs116855232 (*3): not on your array

CPIC CPIC (thiopurines 2018) · CPIC: thiopurines, TPMT & NUDT15

Traits

Well-replicated, benign wellness traits that clear our evidence gate: catalogued in the GWAS Catalog, genome-wide significant, and replicated across independent studies. Each is a tendency, not a verdict.

Read from your file: 5 of 23. The other 18 had no variant reported in your file, so they’re read as the common (reference) genotype — an inference, not a measurement (see each card’s note).

ALDH2 Alcohol flush response Flush likely

Whether you tend to flush (going red, warm and sometimes queasy) soon after drinking alcohol.

Your genotype: G/A (rs671)
Most-associated outcome: Flush likely

One inactive (A) allele: ALDH2 works at reduced capacity, so acetaldehyde builds up and flushing, warmth or nausea after alcohol are likely. This matters for health, not just comfort: acetaldehyde is a recognised carcinogen, and with this genotype drinking raises the risk of alcohol-associated oesophageal and head-and-neck cancer above average. (The same enzyme activates the heart drug nitroglycerin, which can work less well in ALDH2-deficient people.) Information, not advice.

Why we include this: the evidence

Source: Functional variant: Crabb et al. 1989 (J Clin Invest) · PMID:2562960
Significance: Below genome-wide significance
Replication: Crabb et al. 1989 demonstrated biochemically that the ALDH2*2 allele (Glu504Lys) is dominant-negative: heterozygotes have markedly reduced enzyme activity. The variant is extensively replicated across East-Asian cohorts and has been shown to confer risk of alcohol-associated cancers; A allele frequency in gnomADg:eas = 0.2249.
Where established: The A allele is common in East-Asian ancestry (gnomADg:eas ~22%) and nearly absent in European and African ancestry (gnomADg:ALL ~0.8%)
Effect: The A allele dominantly reduces ALDH2 activity, causing the flush response

ALDH2 clears acetaldehyde, alcohol's toxic first breakdown product. The Lys504 (A) enzyme is nearly inactive and acts as a dominant-negative inhibitor of the wild-type subunit, so even one A allele substantially reduces tetrameric enzyme activity, allowing acetaldehyde to accumulate and trigger flushing.

MedlinePlus Genetics: ALDH2 gene · NIH/PMC: acetaldehyde, ALDH2 deficiency and alcohol-associated cancer

ADH1B Alcohol metabolism speed (ADH1B) Standard-speed metaboliser

How quickly your liver converts alcohol (ethanol) into acetaldehyde, the first step in breaking down a drink, shaped largely by the ADH1B variant you carry.

Your genotype: T/T (rs1229984)
Most-associated outcome: Standard-speed metaboliser

Two T alleles: the ADH1B*1 genotype. Ethanol is oxidised to acetaldehyde at a standard rate; you are unlikely to experience ADH1B-driven flushing. Note: ALDH2 (a separate gene) handles the next step; if you carry the ALDH2 flush variant, that still applies.

Why we include this: the evidence

Source: Functional variant: Edenberg & McClintick 2018 (Alcohol Clin Exp Res) review; original ADH1B*2 characterisation Bosron & Li 1986, Hurley et al. 1990 · PMID:30320893
Significance: Below genome-wide significance
Replication: The ADH1B*2 allele (His48Arg, C allele at rs1229984) produces an alcohol dehydrogenase beta2 subunit with 40–100x higher Vmax than the beta1 (T allele) form. This was biochemically characterised by Jörnvall et al. 1984 and Hurley et al. 1990 and has been replicated in hundreds of pharmacokinetic and epidemiological studies. The C allele reaches ~30% in East-Asian populations (gnomADg:EAS = 0.2961) and ~3.6% in European (gnomADg:NFE = 0.0357). GWAS confirm strong protective associations with alcohol dependence and aerodigestive cancer risk.
Where established: The C (fast/ADH1B*2) allele is common in East-Asian ancestry (~30%) and much rarer in European and African ancestry (~4% and ~1% respectively); maf reported as gnomADg:EAS (the population where it is most common)
Effect: The C allele (Arg48, ADH1B*2) is dominant for fast ethanol oxidation: even one copy substantially accelerates acetaldehyde production after drinking

ADH1B encodes the beta subunit of the class-I liver alcohol dehydrogenase that performs the first oxidative step (ethanol → acetaldehyde) in alcohol metabolism. The His48Arg (T>C) substitution stiffens the active site in a way that dramatically increases catalytic rate. Faster ADH1B means acetaldehyde accumulates more rapidly after drinking, producing nausea, flushing and discomfort, which acts as a natural deterrent to heavy drinking. The C allele is associated with protection against alcohol use disorder and alcohol-related cancers, but acetaldehyde is itself a carcinogen, so rapid production without equally fast ALDH2 clearance carries its own risks.

The marker for this trait wasn’t found in your file, so it reads as the reference genotype. A variant file can’t prove that position was covered, so treat this as an inference. Traits are tendencies, not certainties.

Edenberg & McClintick 2018: ADH1B and alcohol use disorders review (Alcohol Clin Exp Res) · MedlinePlus Genetics: ADH1B gene

OR2M7 region Asparagus urine smell detection More able to smell it

Whether you can smell the distinctive odour some people produce in urine after eating asparagus.

Your genotype: A/A (rs4481887)
Most-associated outcome: More able to smell it

At least one A allele is associated with a greater ability to detect the characteristic asparagus-urine odour. A harmless quirk of smell.

Why we include this: the evidence

Source: Functional variant: Markt et al. 2016 (BMJ) · PMID:27965198
Significance: Below genome-wide significance
Replication: Markt et al. 2016 (BMJ, N=6,909) performed a GWAS of asparagus anosmia and identified rs4481887 in an olfactory-receptor gene cluster as the top hit; Eriksson et al. 2010 (PLoS Genet, PMID:20585627, N=9,126) first reported this association from a 23andMe web-based study. The trait is olfactory-cluster-localised and the A allele (smell-detected) reaches 20-31% in European populations.
Where established: Established mainly in European-ancestry cohorts
Effect: The A allele is associated with a greater ability to detect the asparagus-urine odour

rs4481887 lies within a cluster of olfactory-receptor genes (including OR2M7) on chromosome 1; these receptors are thought to detect the sulphur-containing methanethiol compounds asparagus metabolism produces.

GWAS Catalog: asparagus anosmia

TAS2R38 Bitter taste sensitivity (TAS2R38) Likely non-taster

Whether bitter compounds, including in coffee, broccoli, and certain medicines, tend to taste strongly bitter to you, shaped mainly by the TAS2R38 haplotype you carry.

Your genotype: C/C; G/G (rs713598)
Most-associated outcome: Likely non-taster

Both haplotypes are AVI: the genotype associated with much weaker bitter detection at TAS2R38. Broccoli, raw kale and black coffee may taste mild where others find them harsh. This is a genetic tendency, not a guarantee; habit and other taste receptors still shape what you notice.

Why we include this: the evidence

Source: Functional variant: Kim et al. 2003 (Science) · PMID:12595690
Significance: Below genome-wide significance
Replication: Kim et al. 2003 positionally cloned TAS2R38 as the receptor underlying PTC/PROP bitter taste; the three-SNP PAV/AVI haplotype has been replicated in dozens of independent cohorts. The taster (PAV) and non-taster (AVI) haplotypes account for the majority of the normal population variance in bitter sensitivity. rs713598 and rs1726866 MAFs in gnomADg:ALL are ~0.447 and ~0.472 respectively, confirming both as common variants.
Where established: PAV and AVI haplotypes are found across all major ancestry groups; relative frequency varies (AVI is rarer in some East-Asian populations)
Effect: The PAV haplotype (G at rs713598 / G at rs1726866) confers bitter taste sensitivity; AVI (C/A) is non-tasting; heterozygotes are intermediate

TAS2R38 encodes a bitter taste receptor. The PAV form (Pro49/Ala262/Val296) is correctly folded and signals in response to phenylthiocarbamide, PROP and other bitter glucosinolates. The AVI form is non-functional for these ligands. Bitter sensitivity influences diet preferences and perception of off-notes in vegetables and beverages.

Kim et al. 2003: positional cloning of TAS2R38 in Science · MedlinePlus Genetics: Taste

CYP1A2 Caffeine metabolism Slower metaboliser

How quickly your liver tends to clear caffeine, set largely by the CYP1A2 enzyme.

Your genotype: A/C (rs762551)
Most-associated outcome: Slower metaboliser

You carry at least one C allele, associated with slower caffeine clearance: caffeine tends to linger longer, so the same cup can feel stronger or disturb sleep more. A modest tendency, not a rule; habit and dose matter more day to day.

Why we include this: the evidence

Source: PharmGKB · PA27093
Significance: Below genome-wide significance
Replication: CYP1A2 *1F (rs762551) is the canonical PharmGKB marker for CYP1A2 inducibility (gene PA27093); slower vs faster caffeine clearance by genotype is documented across multiple pharmacokinetic studies.
Where established: Studied across several ancestries; effect sizes are modest
Effect: The A allele is associated with faster (more inducible) CYP1A2 activity; C-allele carriers tend to be slower metabolisers

rs762551 marks the CYP1A2 *1F haplotype; CYP1A2 performs the bulk of caffeine breakdown, and its inducibility differs by genotype (and by smoking).

MedlinePlus Genetics: CYP1A2 gene

CASC16 locus Chronotype (morning vs evening tendency) Morning tendency

A genetic tendency toward being a morning person or an evening person, shaped partly by a variant in the CASC16 region near chromosomal region 16q12.

Your genotype: A/A (rs12927162)
Most-associated outcome: Morning tendency

Two A alleles: the genotype associated with preferring earlier rising and peak alertness earlier in the day. A tendency, not a certainty: sleep hygiene, light exposure and social schedules shape your actual sleep timing far more than this single variant.

Why we include this: the evidence

Source: GWAS Catalog · GCST003429, GCST007576
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Hu et al. 2016 (Nat Commun, GCST003429, N=89,283 Europeans) identified rs12927162-A as significantly associated with morning chronotype (OR=1.099, p=2e-12). Jones et al. 2019 (Nat Commun, GCST007576, N=697,832 Europeans) independently confirmed the locus with a larger beta (p=2e-32). The A allele consistently marks morning preference across both studies. gnomADg:ALL minor allele G frequency = 0.1914.
Where established: Characterised primarily in European-ancestry cohorts; replication in other ancestries is limited for this specific locus
Effect: The A allele is associated with morning preference; the G allele is associated with a tendency toward eveningness

rs12927162 sits in an intergenic region of the 16q12 gene desert (CASC16 locus), approximately 100 kb downstream of TOX3. The mechanism is not fully resolved; the region may harbour regulatory elements influencing circadian-clock gene networks. Chronotype is a polygenic trait shaped by many loci. This single variant explains only a fraction of individual variation. External factors such as light exposure, caffeine, age and social schedules dominate day-to-day timing.

Hu et al. 2016: chronotype GWAS (GCST003429, PMID:26835600) · Jones et al. 2019: chronotype GWAS in 697,828 individuals (GCST007576, PMID:30696823)

OR6A2 Cilantro (coriander) soapy taste More likely to perceive soapy taste

Whether fresh cilantro tends to taste soapy to you, linked to a smell-receptor gene cluster.

Your genotype: C/C (rs72921001)
Most-associated outcome: More likely to perceive soapy taste

At least one C allele is associated with a modestly higher chance of finding cilantro soapy. The effect is small: culture and exposure matter at least as much.

Why we include this: the evidence

Source: Functional variant: Eriksson et al. 2012 (Flavour) · DOI:10.1186/2044-7248-1-22
Significance: Below genome-wide significance
Replication: Eriksson et al. 2012 (Flavour; preprint arXiv:1209.2096) identified rs72921001 near OR6A2 as the lead variant for cilantro soapy taste in a discovery cohort of 14,604 European-ancestry participants and replicated it in a distinct set of 11,851 (lead p=6.4e-9, OR=0.81 per A allele, i.e. the A allele is protective, so the C allele is the soapy-associated allele). Effect is modest; the locus sits in a cluster of olfactory receptor genes implicated in aldehyde perception.
Where established: Established mainly in European and South Asian ancestry cohorts; effect is modest and taste perception is also shaped by culture and exposure
Effect: The C allele is associated with a higher chance of perceiving cilantro as soapy

rs72921001 lies in a cluster of olfactory-receptor genes (including OR6A2) on chromosome 11 that detect the aldehydes giving cilantro its aroma; variant likely affects receptor sensitivity to these compounds.

Eriksson et al. 2012, Flavour: A genetic variant near olfactory receptor genes influences cilantro preference (preprint) · MedlinePlus Genetics: Genes and smell

AHR Coffee consumption tendency (AHR) Lower-intake tendency

A genetic tendency to drink more or fewer cups of coffee per day on average, shaped partly by the aryl hydrocarbon receptor gene near this variant.

Your genotype: T/T (rs4410790)
Most-associated outcome: Lower-intake tendency

Two T alleles: the genotype linked to slightly lower habitual coffee intake. A gentle statistical association, not a reason to drink more or less. Your body's response to caffeine (CYP1A2 genotype, adenosine receptors, sleep) shapes the experience far more.

Why we include this: the evidence

Source: GWAS Catalog · GCST001032, GCST002650
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Cornelis et al. 2011 (PLoS Genet, GCST001032, N=47,431 Europeans) identified rs4410790 near AHR as a top locus for habitual caffeine intake (p=2e-19); Cornelis et al. 2015 (Mol Psychiatry, GCST002650, N=91,462+30,062 Europeans) confirmed the AHR locus for coffee cups per day. gnomADg:ALL MAF of T allele = 0.4586.
Where established: Characterised primarily in European-ancestry cohorts; the AHR-region signal for coffee intake has been observed in additional populations
Effect: The C allele is associated with higher habitual coffee intake (more cups per day); the T allele is associated with lower intake

rs4410790 lies near AHR (aryl hydrocarbon receptor), a transcription factor that induces CYP1A2 and other metabolic genes. The AHR pathway modulates caffeine clearance and the brain's response to coffee's aromatic compounds. Individuals with higher AHR-mediated metabolism clear caffeine faster, feel less stimulated per cup and tend to drink more. This is a behavioural tendency from a brain–metabolism interaction; habit, culture and stress all override the genetic signal.

Cornelis et al. 2011: GWAS of caffeine intake (GCST001032) · MedlinePlus Genetics: AHR gene

ACKR1 Duffy blood-group antigen (malaria resistance & neutrophil baseline) Duffy-positive

Whether your red cells carry the Duffy antigen. The 'null' result is common in people of African genetic ancestry and brings two unrelated, well-established effects: resistance to Plasmodium vivax malaria, and a naturally lower normal neutrophil count.

Your genotype: T/T (rs2814778)
Most-associated outcome: Duffy-positive

Your red cells carry the Duffy antigen: the common result outside African-ancestry populations. The malaria-resistance and neutrophil effects below do not apply to you from this variant.

Why we include this: the evidence

Source: GWAS Catalog · GCST001302, GCST004620
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: A textbook, strongly replicated functional regulatory variant; confirmed in GCST001302 (Crosslin 2011, eMERGE leukocyte count, N=13,533, p=7e-55) and GCST004620 (Astle 2016, UK Biobank basophil+neutrophil count, N=170,143, p=2e-12)
Where established: The C (null) allele is common in people of West/Central African genetic ancestry and uncommon elsewhere. Ancestry is not race, and allele frequencies vary continuously across people. This result applies to anyone who carries the variant, however they identify.
Effect: C/C silences ACKR1 on red cells (Duffy-null), giving P. vivax resistance and a lower neutrophil baseline

The C allele disrupts a GATA-1 binding site, so the Duffy antigen/chemokine receptor is not made on red cells. Plasmodium vivax uses that receptor to invade red cells, so Duffy-null cells resist it. The same biology is linked to a constitutionally lower neutrophil count.

MedlinePlus Genetics: ACKR1 gene

ABCC11 Earwax type & body odour Dry earwax

A single ABCC11 variant that sets whether your earwax is wet or dry, and tracks with how much underarm body odour you tend to produce.

Your genotype: T/T (rs17822931)
Most-associated outcome: Dry earwax

Two T alleles: dry, flaky earwax and a tendency toward noticeably less underarm body odour, because the apocrine glands make fewer of the compounds skin bacteria turn into smell. Entirely benign; just a difference.

Why we include this: the evidence

Source: Functional variant: Yoshiura et al. 2006 (Nat Genet) · PMID:16444273
Significance: Below genome-wide significance
Replication: Confirmed in multiple populations and by functional biochemical studies; the T/T genotype reliably predicts dry earwax and reduced apocrine secretion across ethnic groups. In East-Asian populations (gnomADg:eas ~84%) the T allele is the major allele.
Where established: The dry (T) allele is common in East-Asian ancestry (gnomADg:eas ~84%) and rarer in European and African ancestry (gnomADg:ALL ~14%)
Effect: The T allele is recessive: T/T gives dry earwax and reduced odour; a C allele gives wet earwax

ABCC11 encodes an ATP-binding cassette transporter expressed in earwax and apocrine sweat glands. The 538G>A substitution (Gly180Arg; T allele) causes protein misfolding and degradation, disabling the transporter and giving dry flaky earwax and less underarm odour.

MedlinePlus Genetics: ABCC11 gene

HERC2 Eye colour (blue vs brown) Brown-eye associated

The main common genetic switch behind blue versus brown eyes, though eye colour is polygenic, so this is a strong hint, not a verdict.

Your genotype: A/A (rs12913832)
Most-associated outcome: Brown-eye associated

Two reference (A) alleles: strongly associated with brown eyes. Other genes fine-tune the shade, but blue eyes are unlikely with this genotype.

Why we include this: the evidence

Source: GWAS Catalog · GCST000685, GCST000710
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: The single most replicated eye-colour locus; explains a large share of blue/brown variation; independently confirmed in GCST000685 (Liu 2010, N=9,494) and GCST000710 (Eriksson 2010, N=9,126)
Where established: Best established in European-ancestry populations, where blue/brown variation is common
Effect: The G allele is recessive for blue; G/G is strongly associated with blue eyes, A/_ with brown

rs12913832 lies in an intron of HERC2 that regulates the neighbouring OCA2 pigment gene; the G allele lowers OCA2 expression in the iris, reducing melanin and favouring blue eyes.

MedlinePlus Genetics: Eye color

IRF4 Freckling tendency (IRF4) Less prone to freckling

A genetic tendency toward freckles and fair, sun-sensitive skin, shaped by a well-studied variant in an enhancer of the IRF4 gene in pigment cells.

Your genotype: C/C (rs12203592)
Most-associated outcome: Less prone to freckling

Two C alleles: the genotype least associated with freckling at IRF4. Skin tends to be less freckle-prone, though sun exposure and other pigment genes still matter.

Why we include this: the evidence

Source: Functional variant: Praetorius et al. 2013 (Cell) · PMID:24267888
Significance: Below genome-wide significance
Replication: Praetorius et al. 2013 (Cell, PMID:24267888) showed in melanocytes, zebrafish and mice that rs12203592 lies within an enhancer of IRF4: the T allele impairs binding of TFAP2A, which with the melanocyte master regulator MITF drives the enhancer, and IRF4 cooperates with MITF to activate tyrosinase (TYR). The variant's association with freckles, sun sensitivity, blue eyes and brown hair was first reported in large pigmentation GWAS (Han 2008; Eriksson 2010) and the mechanism was then established functionally in vivo.
Where established: Established mainly in European-ancestry cohorts; the T allele and freckling are most common in lighter-skinned populations. Freckling also depends heavily on sun exposure and age.
Effect: The T allele is associated with more freckling and fairer, more sun-sensitive skin; the C allele with less.

rs12203592 sits in a melanocyte enhancer in intron 4 of IRF4. The T allele weakens TFAP2A binding, reducing IRF4 expression; IRF4 normally cooperates with MITF to switch on tyrosinase (TYR), the rate-limiting melanin-synthesis enzyme. Less IRF4 means less even melanin production, which presents as freckles and lighter, sun-sensitive skin (Praetorius et al. 2013).

Praetorius et al. 2013, Cell: A polymorphism in IRF4 affects human pigmentation · MedlinePlus Genetics: IRF4 gene

FUT2 FUT2 secretor status (norovirus resistance, gut microbiome, B12) Secretor

Whether you secrete blood-group sugars into saliva, the gut and other body fluids. Non-secretors resist the dominant strains of norovirus and tend to have a different gut microbiome and higher serum vitamin B12.

Your genotype: G/G (rs601338)
Most-associated outcome: Secretor

You secrete blood-group sugars into body fluids: the common result. Most norovirus strains can attach, and your gut microbiome and B12 profile follow the typical pattern for this gene.

Why we include this: the evidence

Source: Functional variant: Carlsson et al. 2009 (PLoS One) · PMID:19440360
Significance: Below genome-wide significance
Replication: The FUT2 G428A (c.461G>A, p.Trp154Ter) nonsense variant has been studied extensively; homozygous carriers lack FUT2 enzyme activity and are non-secretors. Carlsson 2009 confirmed protection against symptomatic norovirus GII.4 in a clinical cohort. The A allele frequency in gnomADg:nfe = 0.4776, confirming it as a common polymorphism in Europeans.
Where established: rs601338 is the common non-secretor allele in people of European genetic ancestry. Other populations carry different non-secretor alleles this single marker does not capture (for example se357 in East Asia), so a 'secretor' call from this marker alone is not a global determination. Ancestry is not race; this applies to anyone carrying the variant.
Effect: A/A removes FUT2 enzyme activity → non-secretor

FUT2 adds blood-group sugars to mucosal surfaces. The A allele (Trp154Ter stop codon) inactivates the enzyme, so A/A people are non-secretors. Many gut pathogens, notably norovirus GII.4, need those sugars to attach, so non-secretors resist them.

MedlinePlus Genetics: FUT2 gene

KITLG Hair colour shade (KITLG) Darker hair tendency

A genetic tendency toward lighter (blond) versus darker (brown or black) hair, shaped partly by a regulatory variant near the KITLG gene on chromosome 12.

Your genotype: T/T (rs12821256)
Most-associated outcome: Darker hair tendency

Two T alleles: the genotype at this KITLG locus associated with darker hair shades (brown or black). This is the most common combination (~87% of people globally). The rest of your hair-colour genetics, including MC1R and HERC2/OCA2, determine whether your hair is light brown, dark brown, or black.

Why we include this: the evidence

Source: GWAS Catalog · GCST006988, GCST006989
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Morgan et al. 2018 (Nat Commun, PMID:30531825) genome-wide study of hair colour in 323,317 UK Biobank participants: rs12821256-C associated with blond vs brown/black (GCST006988, p=4×10^-30); same SNP replicated in brown vs black comparison (GCST006989, N=283,920). The KITLG locus is one of several replicated hair-colour loci alongside MC1R, HERC2/OCA2, and IRF4. gnomADg:ALL MAF for the C (blond) allele = 0.0685.
Where established: Best characterised in European-ancestry cohorts; blond hair is most common in Northern European populations
Effect: The C allele (minor allele, ~7% global frequency) is associated with lighter, blond hair; the T allele (reference, ~93% frequency) is associated with darker brown or black hair

rs12821256 lies in a regulatory region upstream of KITLG (also known as SCF, stem cell factor), which encodes a ligand that supports melanocyte survival and migration. The C allele is thought to reduce KITLG expression in hair follicles, lowering melanin production and favouring blond colouring. Hair colour is highly polygenic; MC1R, HERC2/OCA2, IRF4 and dozens of other loci jointly determine the specific shade.

Morgan et al. 2018: Hair colour GWAS in UK Biobank (Nat Commun) · MedlinePlus Genetics: Hair color

EDAR Hair thickness & shape European/African-typical hair fibre

A tendency toward thicker, straighter hair strands, influenced by a well-studied variant in EDAR.

Your genotype: A/A (rs3827760)
Most-associated outcome: European/African-typical hair fibre

Two A alleles: the ancestral genotype, common outside East Asia, associated with the typical range of hair-fibre thickness for those ancestries.

Why we include this: the evidence

Source: Functional variant: Kamberov et al. 2013 (Cell) · PMID:23415220
Significance: Below genome-wide significance
Replication: EDAR 370A (rs3827760) is the classic functional hair-morphology variant: identified for East-Asian hair thickness (Fujimoto et al. 2008) and shown causal in a mouse model expressing the selected EDAR allele (Kamberov et al. 2013, Cell). The derived G allele is at high frequency in East-Asian and Native-American ancestry.
Where established: The G (derived) allele is common in East-Asian and Native-American ancestry and rare in European/African ancestry. Read this trait with ancestry in mind
Effect: The G (370Ala) allele is associated with thicker, straighter hair fibres and shovel-shaped incisors

rs3827760 changes an amino acid in EDAR, a receptor guiding the development of hair, teeth and sweat glands; the derived allele increases EDAR signalling.

MedlinePlus Genetics: EDAR gene

MCM6 Lactase persistence Likely lactase persistent

Whether your body tends to keep producing lactase, the enzyme that digests the milk sugar lactose, into adulthood.

Your genotype: T/T (rs4988235)
Most-associated outcome: Likely lactase persistent

You carry at least one persistence (T) allele, so you most likely keep digesting lactose comfortably as an adult. This is a tendency, not a guarantee: tolerance also depends on gut bacteria and how much dairy you eat.

Why we include this: the evidence

Source: Functional variant: Enattah et al. 2002 (Nat Genet) · PMID:11788828
Significance: Below genome-wide significance
Replication: One of the most replicated human trait associations; the −13910 C>T enhancer variant was first identified in Finnish and other European cohorts and has since been confirmed in many independent cohorts worldwide. Functional studies show the T allele creates a binding site for Oct-1 transcription factor, maintaining LCT expression into adulthood. MAF is the minor (C / non-persistence) allele frequency in gnomADg:NFE (0.3647); the T / persistence allele is the majority allele in Northern Europeans.
Where established: Best established in Northern European-ancestry populations; the persistence (T) allele reaches ~64% in NFE but is much rarer in East Asian, Middle-Eastern, and most African populations; other persistence variants exist in African and Middle-Eastern populations and are not covered here
Effect: The T allele is dominantly associated with continued lactase production into adulthood

rs4988235 sits in an MCM6 intron that acts as an enhancer of the neighbouring LCT (lactase) gene; the T allele keeps LCT transcribed after weaning via an Oct-1 binding site.

MedlinePlus Genetics: Lactose intolerance

TWIST2 Androgenetic hair thinning tendency (TWIST2) Lower genetic tendency

A genetic tendency toward androgenetic hair thinning (the most common form of hair loss), shaped partly by a regulatory variant near the TWIST2 gene. This reflects a cosmetic tendency, not a disease prediction.

Your genotype: C/C (rs11684254)
Most-associated outcome: Lower genetic tendency

Two C alleles: the genotype at this TWIST2 locus associated with lower androgenetic hair-thinning tendency from this variant. Hair thinning is shaped by many other genetic and hormonal factors; this is one locus among dozens. Age, testosterone metabolism, and lifestyle also play a large role.

Why we include this: the evidence

Source: GWAS Catalog · GCST007020, GCST006661
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Yap et al. 2018 (Nat Commun, PMID:30573740, GCST007020, N=205,327 European males) identified rs11684254-G as one of the strongest genome-wide signals for male-pattern baldness (p≈2×10^-308, beta=increase); independently confirmed in Hagenaars et al. 2017 (PLoS Genet, PMID:28196072, GCST006661, N=52,874 British males, p≈1×10^-40, beta=increase). Also replicated in Hillmer 2018 (GCST007815, N=22,518, p=1×10^-39, β=0.29). The TWIST2 locus is one of the most consistently replicated autosomal loci for androgenetic alopecia. gnomADg:ALL MAF for the G allele = 0.4396.
Where established: Best characterised in European-ancestry males; androgenetic alopecia is universal but prevalence and genetic architecture vary by ancestry
Effect: The G allele (rs11684254-G, ~44% global frequency) is associated with greater tendency to develop androgenetic hair thinning; the C allele is associated with lower tendency at this locus

rs11684254 lies upstream of TWIST2 (Twist Family BHLH Transcription Factor 2), a regulatory transcription factor involved in follicular development and stem cell differentiation. The G allele is thought to alter TWIST2 expression in hair follicles, influencing the miniaturisation process characteristic of androgenetic alopecia. The androgen-receptor pathway (driven by dihydrotestosterone) is the main driver; the TWIST2 locus likely modulates follicle sensitivity. Hair loss is highly polygenic (dozens of loci contribute alongside this one), and lifestyle, age, and androgens strongly mediate the trait.

Yap et al. 2018: Dissection of male pattern baldness (Nat Commun) · Hagenaars et al. 2017: Genetic prediction of male pattern baldness (PLoS Genet)

ACTN3 Muscle fibre type (ACTN3) Endurance-associated

A common variant in the ACTN3 "speed gene" that nudges muscle toward power/sprint vs endurance tendencies.

Your genotype: T/T (rs1815739)
Most-associated outcome: Endurance-associated

Two stop (T) alleles: you make no α-actinin-3, which is completely benign and common. This genotype is slightly more frequent in endurance athletes than power athletes. A tendency only; trainability dominates.

Why we include this: the evidence

Source: Functional variant: Yang et al. 2003 (Am J Hum Genet) · PMID:12879365
Significance: Below genome-wide significance
Replication: One of the most studied muscle-genetics variants. Yang et al. 2003 (Am J Hum Genet, N=429 elite athletes + controls) first showed the R577X null allele (T) is under-represented in sprint/power athletes. Confirmed in many independent cohorts worldwide. The null allele is common: ~18% of people are T/T worldwide (gnomADg:ALL T = 0.3751, so T/T ≈ 14%). Functional and population evidence is strong; this is not a statistical GWAS association but a protein-null variant with a well-characterised phenotypic shift.
Where established: Studied across multiple ancestries; the X (T) allele is common worldwide, with gnomADg:ALL frequency 0.3751
Effect: The functional C allele is over-represented in elite power athletes; T/T removes α-actinin-3 from fast-twitch fibres

rs1815739 introduces a premature stop codon (R577X) in ACTN3, eliminating α-actinin-3 from fast-twitch (type II) muscle fibres. T/T individuals rely entirely on α-actinin-2, a structural shift associated with endurance-leaning muscle characteristics, and entirely benign.

MedlinePlus Genetics: ACTN3 gene

FADS1 Omega fatty acid desaturation (FADS1) Efficient desaturator

How efficiently your body converts short-chain omega-6 and omega-3 fats from food into the longer-chain forms (arachidonic acid, EPA and DHA) that your cells use directly.

Your genotype: G/G (rs174537)
Most-associated outcome: Efficient desaturator

Two G alleles: the genotype linked to more efficient FADS1 desaturase activity. Your body tends to convert plant-based omega-6 and omega-3 fats into the longer-chain forms (arachidonic acid, EPA, DHA) relatively well. This is a tendency; dietary fat intake still matters most.

Why we include this: the evidence

Source: GWAS Catalog · GCST002721, GCST90060989
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Mozaffarian et al. 2013 (PLoS Genet, GCST002721, N=10,421 multi-ancestry) found rs174537-T associated with trans-18:2 (linoleic acid isomer) measurement; a second study (GCST90060989, N=5,662 Pakistani) confirmed FADS1-region association with phosphatidylserine levels (p=4e-20). The FADS1 locus is the most replicated genetic locus for polyunsaturated fatty acid metabolism across dozens of independent cohorts. gnomADg:ALL MAF of T allele = 0.2888.
Where established: Effect replicated across European, African, Asian and mixed-ancestry cohorts; T allele is common in all major populations
Effect: The T allele is associated with altered FADS1 desaturase activity and higher proportions of 18-carbon fatty acid precursors relative to long-chain products (lower elongation/desaturation efficiency); G allele is associated with more efficient conversion

rs174537 is the lead tagging SNP for the FADS1–FADS2 gene cluster on chromosome 11. FADS1 (delta-5 desaturase) and FADS2 (delta-6 desaturase) catalyse the rate-limiting steps converting linoleic acid (18:2n-6) to arachidonic acid (20:4n-6), and alpha-linolenic acid (18:3n-3) to EPA (20:5n-3) and DHA (22:6n-3). The T-allele haplotype is associated with reduced desaturase activity, so T/T individuals tend to have lower arachidonic acid and long-chain n-3 PUFA and higher precursor fatty acids from diet. This affects inflammatory signalling, membrane composition and cardiovascular markers, all tendencies, not diagnoses.

MedlinePlus Genetics: FADS1 gene · Mozaffarian et al. 2013: GWAS of circulating fatty acids (GCST002721)

ZEB2 region Photic sneeze reflex (ACHOO) More likely to photic-sneeze

Whether bright light tends to make you sneeze: the so-called photic sneeze reflex.

Your genotype: C/C (rs10427255)
Most-associated outcome: More likely to photic-sneeze

At least one C allele is associated with a higher chance of the photic sneeze reflex: sneezing when moving into bright light. A harmless quirk.

Why we include this: the evidence

Source: GWAS Catalog · GCST000706, GCST007687
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Identified and independently replicated in GCST000706 (Eriksson 2010, 23andMe, N=9,126, European) and GCST007687 (Chinese ancestry GWAS, N=3,417, p=6e-20)
Where established: Established mainly in European-ancestry cohorts; independently replicated in Chinese cohort
Effect: The C allele is associated with a higher chance of sneezing in response to bright light

rs10427255 sits near ZEB2; the reflex is thought to involve cross-wiring of visual and sneeze pathways, though the exact biology is still being studied.

GWAS Catalog: photic sneeze reflex

MC1R Red hair and fair skin tendency (MC1R) No R allele detected

A genetic tendency toward red or auburn hair colouring and fair skin, shaped by two classic MC1R loss-of-function variants known as 'R' alleles. Carrying one or two R alleles shifts the hair follicle's pigment balance toward warm, reddish tones and increases freckling tendency.

Your genotype: C/C; C/C (rs1805007)
Most-associated outcome: No R allele detected

No R alleles at these two MC1R positions: the genotype associated with the lowest probability of red or auburn hair from this locus. Other pigmentation genes (HERC2/OCA2, IRF4, KITLG) determine your specific shade, but warm red tones from MC1R are unlikely. The majority of people carry this combination.

Why we include this: the evidence

Source: Functional variant: Valverde et al. 1995 (Nature Genetics) · PMID:7581459
Significance: Below genome-wide significance
Replication: Valverde et al. 1995 (Nat Genet, PMID:7581459) identified MC1R R allele variants in >80% of individuals with red hair or fair non-tanning skin but <20% of dark-haired individuals, establishing these as the primary common genetic determinants of red pigmentation. Hundreds of subsequent studies across diverse cohorts confirm R151C (rs1805007) and R160W (rs1805008) as the two most common and most penetrant red-hair R alleles. The GWAS Catalog documents rs1805007-T with OR=12.47 for hair colour and OR=4.37 for freckles (p values ≤ 2×10^-55). gnomADg:ALL MAF for rs1805007-T ≈ 4.6%; rs1805008-T ≈ 4.6%.
Where established: R alleles are common in populations of Northern European ancestry, especially Irish, Scottish, and British; rare in East Asian and sub-Saharan African populations
Effect: Each T allele (R151C or R160W) reduces MC1R signalling, shifting pigment production from dark eumelanin toward reddish pheomelanin; carrying one or two R alleles raises the probability of red or auburn hair and fair skin with freckling tendency

MC1R encodes the melanocortin-1 receptor, which controls the eumelanin/pheomelanin switch in melanocytes. Binding of α-MSH activates the receptor, favouring dark eumelanin. The R151C and R160W substitutions impair receptor function, tipping the balance toward reddish pheomelanin. The result is a lighter hair and skin phenotype with increased sensitivity to UV and a tendency for warm hair tones. Hair colour is polygenic: HERC2/OCA2, IRF4, KITLG and other loci also contribute, so these two variants are a strong signal, not a complete predictor.

Valverde et al. 1995: MC1R variants and red hair (Nature Genetics) · MedlinePlus Genetics: Hair color

FUT2 Vitamin B12 tendency (FUT2) Lower-B12 tendency

A genetic influence on circulating vitamin B12, linked to the FUT2 gene that also governs secretor status: non-secretors tend to have higher serum B12.

Your genotype: G/G (rs602662)
Most-associated outcome: Lower-B12 tendency

Two G alleles: associated with a modest downward nudge in serum vitamin B12 at this locus. Most people with this genotype have perfectly adequate B12 with a normal diet; this variant is one small piece of the picture, not a reason to worry without a blood test.

Why we include this: the evidence

Source: GWAS Catalog · GCST90277442, GCST000358
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Grarup et al. 2013 (PLoS Genet, GCST90277442, N=38,229 Danish/Icelandic) confirmed rs602662-A as the top FUT2-region hit for vitamin B12 (p=2e-139, increase); Hazra et al. 2009 (Nat Genet, GCST000358, N=3,620 Europeans) first reported this association (p=3e-20, beta=+49.77 pg/ml). The FUT2 locus is among the most robustly replicated B12 loci. gnomADg:ALL MAF of A allele = 0.4598.
Where established: Well-characterised in European and Scandinavian ancestry cohorts; the A allele frequency varies by population
Effect: The A allele is associated with higher serum vitamin B12; G allele (non-secretor haplotype region) is associated with lower circulating B12

rs602662 tags the FUT2 non-secretor haplotype. FUT2 adds fucose sugars to gut mucosal surfaces; non-secretor status (A allele) alters the intestinal microbiome and gut physiology in ways that increase vitamin B12 absorption or reduce bacterial competition for the vitamin. The FUT2 locus is distinct from intrinsic-factor deficiency and pernicious anaemia. This is a common-variant modulation of B12 status within the normal range.

Grarup et al. 2013: Vitamin B12 and folate GWAS (GCST90277442) · MedlinePlus Genetics: FUT2 gene

GC Vitamin D tendency (GC / VDBP) Higher-tendency

A genetic nudge toward lower or higher circulating vitamin D, set partly by how efficiently your body carries the vitamin through your bloodstream.

Your genotype: T/T (rs2282679)
Most-associated outcome: Higher-tendency

Two reference (T) alleles: the genotype associated with somewhat higher circulating vitamin D from this locus. Still no substitute for adequate sun exposure and a good diet; this is a gentle genetic nudge, not a guarantee.

Why we include this: the evidence

Source: GWAS Catalog · GCST000664, GCST005367
Significance: Genome-wide significant (p ≤ 5×10⁻⁸)
Replication: Wang et al. 2010 (Lancet, GCST000664, N=6,722 Europeans) identified rs2282679 in GC as a top locus for 25-hydroxyvitamin D; Manousaki et al. 2017 (PLoS Genet, GCST005367, N=79,366 initial + 42,757 replication) confirmed this as one of the strongest common vitamin D loci. gnomADg:ALL MAF of G allele = 0.2176.
Where established: Effect well characterised in European-ancestry cohorts; replicated in other ancestries but effect size varies
Effect: The G (minor) allele at rs2282679 is associated with lower 25-hydroxyvitamin D levels; T/T carriers tend toward higher circulating vitamin D

rs2282679 lies in the GC gene, which encodes the vitamin D-binding protein (VDBP / DBP) that transports 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D through the circulation. The G allele is associated with a structural variant that reduces the binding efficiency or circulating concentration of VDBP, lowering transported vitamin D. This is a tendency: sun exposure, diet and supplementation remain the dominant determinants of actual status.

MedlinePlus Genetics: GC gene (vitamin D binding protein) · Wang et al. 2010: Common genetic determinants of vitamin D insufficiency (GCST000664)

ABO blood type

Likely · not a blood test

Your likely ABO blood group, inferred from three positions in the ABO gene. This is genetics, not a blood test. It is a strong indication for most people but not a clinical result.

ABOgroup not determinedTier 2 · Well-supported

Your genetics most likely give blood group O: no functional A or B allele (two copies of the O deletion). O is the most common group worldwide and, separately, group O is linked to a modestly lower risk of severe Plasmodium falciparum malaria and of some clotting events (small population averages, not personal predictions).

Important: This is a likely blood group inferred from DNA, not a measured one. Rare ABO subgroups, the cis-AB and weak-A/B variants, and the messy O deletion mean genetics can occasionally disagree with a real blood test, so confirm with an actual blood test, and never use this for transfusion or any medical decision.

No functional ABO variant was found, so this reads as the reference, which on GRCh38 is blood group O. A variant file can't prove those positions were covered, so treat this as an inference, not a confirmed O.

2026-06-07 · NCBI dbSNP: rs8176719 (ABO 261delG) · Yamamoto: Molecular genetics of the ABO blood group system (Annals of Blood)

Polygenic scores

Tendency · not a diagnosis

Reveal my Atrial fibrillation score: sensitive, opt-in

Not reportable Atrial fibrillation 142-variant score (Frederiksen et al., Heart 2023) Tier 2 · Well-supported

Examined, not reportable — only 0 of 142 scoring variants (0%) were found in your file, below the 50% we require to place you on this score’s distribution. This is a coverage gap, not a result.

A polygenic score adds up many small-effect variants into a single statistical tendency. It is not a measurement, not a prediction of whether you will develop the condition, and not a diagnosis. Most of the risk for a complex disease comes from the rest of your genome, your environment, and chance — none of which this number captures.

2026-06-14 · PGS Catalog PGS005159 (restated; analytic European reference distribution under allele-frequency assumptions)

Reveal my Breast cancer score: sensitive, opt-in

Not reportable Breast cancer 65-variant score (Zhang et al., PLoS Med 2018) Tier 2 · Well-supported

Examined, not reportable — only 0 of 65 scoring variants (0%) were found in your file, below the 50% we require to place you on this score’s distribution. This is a coverage gap, not a result.

2026-06-14 · PGS Catalog PGS000051 (restated; analytic European reference distribution under allele-frequency assumptions)

Reveal my Coronary artery disease score: sensitive, opt-in

Not reportable Coronary artery disease 241-variant primary-prevention score (Marston et al., JAMA Cardiology 2023) Tier 2 · Well-supported

Examined, not reportable — only 2 of 241 scoring variants (1%) were found in your file, below the 50% we require to place you on this score’s distribution. This is a coverage gap, not a result.

2026-06-14 · PGS Catalog PGS003438 (restated; analytic European reference distribution under allele-frequency assumptions)

Reveal my Type 2 diabetes score: sensitive, opt-in

Not reportable Type 2 diabetes 47-variant European GWAS-significant SNP score (Liu et al., 2023) Tier 2 · Well-supported

Examined, not reportable — only 0 of 47 scoring variants (0%) were found in your file, below the 50% we require to place you on this score’s distribution. This is a coverage gap, not a result.

2026-06-14 · PGS Catalog PGS004226 (restated; analytic European reference distribution under allele-frequency assumptions)

credibility firewall · exploratory below

Tier 3 · Emerging / Speculative

Frontier

Emerging research

Read from your file: 10 of 38. The other 28 had no variant reported in your file, so they’re read as the common (reference) genotype — an inference, not a measurement (see each card’s note).

ACE Endurance vs power: the ACE 'sport gene' Tags D/D (power-leaning, inferred) Contested

The original 'sport gene': the ACE insertion/deletion has been linked, loosely, to an endurance lean (I) or a power lean (D). We can only INFER it from a nearby tag SNP, and the performance story is contested, a curiosity, never a talent verdict.

Your genotype: G/G (Fitness & performance)
Most-associated reading: Tags D/D (power-leaning, inferred)

Both copies tag the deletion allele: the genotype some studies loosely associate with a power/strength tilt. The link is weak and inferred, not a guarantee of any trait.

How seriously to take this: the evidence

Strength: Contested
Source of the claim: Tag-SNP proxy (rs4343, r²≈0.88 with the I/D in Europeans) for the classic ACE I/D performance literature, which is mixed-to-contested
Effect: Some studies link the ACE I (insertion) allele to a modest endurance lean and the D (deletion) allele to a power/strength lean, but results conflict and effect sizes are tiny. Because rs4343 only tags the actual I/D variant through linkage, any read-out here is a double inference: not a direct measurement. Treat it as a curiosity, not a verdict on athletic type.

ACE encodes angiotensin-converting enzyme, part of the renin-angiotensin system that regulates blood pressure and tissue perfusion. The D-associated allele is loosely tied to higher circulating ACE (hypothesised power/fast-twitch physiology), the I-associated allele to lower ACE (proposed endurance efficiency). The actual causal variant is a 287 bp Alu insertion/deletion that a single-base engine can't type: rs4343 only stands in for it.

Training, recovery, nutrition and sport-specific practice dominate athletic outcomes far more than this variant; single-gene 'sport gene' claims are widely oversold in consumer reports, and this is an inferred, contested one.

What this isn’t: Not a talent test and not a predictor of whether you can become an athlete.

The marker for this entry wasn’t found in your file, so it reads as the reference genotype. A variant file can’t prove that position was covered, so treat this as an inference, and remember these exploratory entries are speculative to begin with.

dbSNP: rs4343 · rs4343 as a homogeneous-assay proxy for ACE I/D (PubMed 18057531)

ACTN3 ACTN3: fast-twitch 'sports gene' (sprint/power vs endurance) Endurance-leaning (X/X) Replicated · small effect

Whether your fast-twitch muscle fibres make alpha-actinin-3. The R577X variant is the most-studied 'athlete gene': real on average across populations, but a tiny influence on any one person next to training.

Your genotype: T/T (Fitness & performance)
Most-associated reading: Endurance-leaning (X/X)

No functional alpha-actinin-3 (~18% of people): fast-twitch fibres lean slightly toward endurance-type properties. Associated on average with a touch less raw power and is more common in some endurance athletes, but plenty of strong, fast X/X people exist.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: PubMed: ACTN3 elite-athlete cohorts (Yang et al. 2003 and replications)
Effect: The X (T) allele is a stop variant: X/X people make no functional alpha-actinin-3 in fast-twitch fibres. R/R is over-represented among elite sprint/power athletes and X/X among some endurance athletes, but the average group difference is small and easily swamped by training, body type and other genes.

Alpha-actinin-3 is a structural protein in fast-twitch (type II) muscle fibres. R577X (rs1815739) truncates it, so the ~18% of people who are X/X produce none and compensate with alpha-actinin-2: a subtle shift toward endurance-type fibre properties, not a deficit.

This is the most replicated result in sports genetics, yet it explains only a sliver of performance variance: training, recovery and dozens of other variants dominate. It does not pick your sport.

What this isn’t: Not a talent test, not a training prescription, and not a ceiling: X/X world-class sprinters and R/R endurance champions both exist.

MedlinePlus Genetics: ACTN3 gene · dbSNP: rs1815739

ADORA2A ADORA2A: caffeine sensitivity & sleep Intermediate Mixed evidence

The adenosine A2A receptor that caffeine blocks. A variant here is linked to how wired or anxious caffeine makes you, and how much it fragments your sleep.

Your genotype: T/C (Sleep & chronotype)
Most-associated reading: Intermediate

One of each allele: an intermediate, and the most common, profile.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: PubMed: caffeine-challenge & sleep studies
Effect: One genotype at rs5751876 is associated on average with more caffeine-induced anxiety and lighter, more disrupted sleep after caffeine. Habitual intake and tolerance shift this strongly.

Caffeine works largely by blocking adenosine A2A receptors (encoded by ADORA2A). Variation in the receptor gene alters individual sensitivity to that blockade, including its anxiogenic and sleep-fragmenting effects.

Caffeine response is shaped at least as much by CYP1A2 metabolism (see your Traits report), tolerance, dose and timing as by this single receptor variant.

What this isn’t: Not medical guidance on caffeine, and not a diagnosis of anxiety or insomnia.

MedlinePlus Genetics: ADORA2A gene · dbSNP: rs5751876

ALDH2 Alcohol flush: acetaldehyde clearance (ALDH2) Reduced clearance, flush-prone Established biology · inferred call

Whether alcohol makes you flush, feel queasy and get a racing heart from even a small drink. One of the best-characterised functional variants in the human genome tilts how fast your body clears acetaldehyde, the toxic first breakdown product of alcohol.

Your genotype: G/A (Substance response)
Most-associated reading: Reduced clearance, flush-prone

One variant copy already cripples most enzyme activity; carriers commonly flush and tolerate alcohol poorly.

How seriously to take this: the evidence

Strength: Established biology · inferred call
Source of the claim: Decades of biochemical work + large East-Asian-ancestry cohorts (PubMed): one of the best-characterised functional human variants
Effect: The A allele (ALDH2*2, a lysine substitution) cripples the enzyme that clears acetaldehyde, so it builds up after drinking: the cause of facial flushing, nausea and a racing heart. A single A copy already produces a large effect because the variant subunit poisons the whole enzyme complex; two copies is more pronounced. It is strongly protective against heavy drinking, and raises upper-aerodigestive cancer risk in people who drink despite the reaction.

ALDH2 is the mitochondrial enzyme that turns acetaldehyde (the immediate product of ethanol breakdown) into harmless acetate. The Glu504Lys substitution sits at the subunit interface and acts dominant-negatively, so even heterozygotes lose most enzyme activity and accumulate acetaldehyde: a known irritant and carcinogen.

The flush is a real biological signal, but its intensity varies a lot between people and with how much you drink: the genotype tells you the tendency, not exactly how you will feel.

What this isn’t: Not a diagnosis of any disease, and not on its own a prediction that you will or won't develop cancer or an alcohol problem, and never a green light to 'drink through' the reaction.

dbSNP: rs671 · Glu504Lys of ALDH2 and risk of human diseases (review, PMC4600480)

ADH1B Alcohol metabolism speed (ADH1B) Standard-rate ADH1B Established biology · inferred call

How fast your liver performs the very first step of breaking down alcohol. A high-activity variant speeds that step dramatically, producing an unpleasant acetaldehyde spike that, on average, nudges carriers toward drinking less.

Your genotype: T/T (Substance response)
Most-associated reading: Standard-rate ADH1B

Slower first-step enzyme (Arg48/Arg48): the more common form in most European-ancestry populations.

How seriously to take this: the evidence

Strength: Established biology · inferred call
Source of the claim: Classic enzyme-kinetics data + multiple large multi-ancestry cohorts (PubMed): one of the most robust findings in alcohol genetics
Effect: The C (His48) allele encodes an enzyme that converts ethanol to acetaldehyde dramatically faster, transiently spiking acetaldehyde and producing an unpleasant reaction that discourages heavy drinking. Carriers show lower rates of alcohol dependence (reported odds ratios around 0.3-0.4 for the protective allele) and tend to drink less. The size of the effect depends on ancestry-specific allele frequency and on the ALDH2 background.

ADH1B is a liver alcohol dehydrogenase that performs the first step of ethanol metabolism. The His48 substitution raises the enzyme's turnover roughly 70-80 fold, so ethanol is oxidised to acetaldehyde faster; the resulting acetaldehyde bump is aversive: especially when ALDH2 clearance is also slow.

This shifts drinking behaviour on average: it is not a switch. Many other genetic and environmental factors shape alcohol use, so individual outcomes vary widely.

What this isn’t: Not a test for, or a diagnosis of, alcohol use disorder, and not a prediction of any individual's drinking on its own.

dbSNP: rs1229984 · ADH1B and alcohol dependence across European and African ancestry (PMC3252425)

BDNF BDNF: Val66Met, learning & neuroplasticity One Met allele Mixed evidence

A growth factor that supports learning, memory and exercise-driven brain plasticity. The Val66Met variant subtly changes how much BDNF is released on demand.

Your genotype: C/T (Cognition & stress)
Most-associated reading: One Met allele

One Met allele: slightly altered activity-dependent BDNF release; population studies show only small, inconsistent average differences on memory or plasticity measures.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: PubMed: neuroimaging & cognition cohorts
Effect: The Met (T) allele is associated with somewhat reduced activity-dependent BDNF secretion and, on average, small differences in episodic memory and exercise-induced plasticity. Findings are inconsistent across populations.

Val66Met (rs6265) sits in the pro-BDNF region and alters intracellular trafficking and activity-dependent release of BDNF at the synapse: the molecule central to long-term potentiation and learning.

Cognitive effects are small, study-dependent and partly ancestry-specific; the Met allele is common and is not a deficit. Sleep, aerobic exercise and learning load move BDNF far more than genotype does.

What this isn’t: Not a measure of memory ability or intelligence, and not a diagnosis of any kind.

MedlinePlus Genetics: BDNF gene · dbSNP: rs6265

BCO1 Beta-carotene converter status (BCO1) Efficient converter Replicated · small effect

Whether your genes make you a more or less efficient converter of plant beta-carotene (the orange pigment in carrots and sweet potato) into active vitamin A. A common variant shifts the balance; total diet and fat intake matter far more for your vitamin A status.

Your genotype: T/T (Nutrition & metabolism)
Most-associated reading: Efficient converter

You carry two copies of the reference allele linked to more efficient conversion of beta-carotene to vitamin A and lower circulating carotenoids.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS (NHGRI-EBI GWAS Catalog), Ferrucci et al. 2009, plus replication of BCO1 carotenoid associations
Effect: The G allele tracks lower BCO1 enzyme efficiency, so beta-carotene is converted to vitamin A more slowly and circulating carotenoid levels run higher. The reference T allele tracks more efficient conversion and lower circulating carotenoids. The site explains only a couple of percent of the variation.

BCO1 is the enzyme that splits dietary beta-carotene into retinal on the way to vitamin A; the variant subtly lowers the enzyme's activity, leaving more unconverted carotenoid in the blood.

A small, replicated effect. Vitamin A status is dominated by what you eat, how much fat is in the meal and overall health, not this single marker. Higher circulating carotenoid is not the same as deficiency.

What this isn’t: Not a diagnosis, not a supplement recommendation, and not a vitamin A deficiency test.

NHGRI-EBI GWAS Catalog, rs6564851 · dbSNP, rs6564851

CADM2 Risk-taking & processing speed (CADM2) Baseline speed / risk tendency Replicated · small effect

A gene that turns up again and again in genome-wide studies of risk-taking, sociability and how fast people process information. The effects are real across huge samples but vanishingly small per person: population statistics, not a personality readout.

Your genotype: C/C (Social & personality)
Most-associated reading: Baseline speed / risk tendency

Two reference copies: the GWAS-baseline genotype for processing speed and self-reported risk-taking. Differences from other genotypes are minute.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: Large GWAS meta-analyses (CHARGE processing-speed, UK Biobank risk-taking) + broader CADM2 behavioural-genetics literature: genome-wide significant, tiny per-variant effect
Effect: The T allele has been tied to slightly faster information-processing speed and, intriguingly, to slightly lower self-reported risk-taking at the same spot. These are statistical tendencies across very large samples, not individual-level predictions: each copy shifts the trait by a tiny fraction of a standard deviation.

CADM2 (cell adhesion molecule 2) helps neurons form and maintain synaptic connections, especially in reward, impulse-control and processing-speed circuits. The variant is intronic and likely nudges CADM2 expression rather than changing the protein; the exact regulatory mechanism is not pinned down.

Each copy shifts the trait by a tiny fraction of a standard deviation; CADM2 associations are polygenic-context effects, and behaviour is overwhelmingly shaped by environment and many other genes.

What this isn’t: Not a 'risk-taking gene', an intelligence test or a personality diagnosis: just one of thousands of common variants nudging population averages.

dbSNP: rs17518584 · GWAS for processing speed implicates CADM2 (Mol Psychiatry 2016)

CYP1A2 Caffeine metabolism: fast or slow (CYP1A2) Intermediate inducibility Mixed evidence

Whether the enzyme that clears most of your caffeine ramps up readily (so caffeine clears fast) or stays lower (so it lingers). A single regulatory variant nudges the dial, but how much coffee you actually drink, plus smoking and medicines, matter far more.

Your genotype: C/A (Substance response)
Most-associated reading: Intermediate inducibility

One high-inducibility allele: an in-between metaboliser profile.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: PubMed: many small-to-medium caffeine and pharmacokinetic studies; widely used by consumer-DNA products, but replication of hard outcomes is patchy
Effect: The A allele is generally tied to a more inducible CYP1A2 enzyme, so AA individuals are often labelled 'fast' caffeine metabolisers and C-carriers 'slower', with caffeine lingering longer. In practice the effect shows up mostly as inducibility (e.g. in smokers or heavy coffee drinkers) and is modest and context-dependent. Reported links between this variant and outcomes like blood pressure or heart-attack risk after coffee are genuinely mixed and should be read cautiously.

CYP1A2 is a liver cytochrome-P450 enzyme that clears about 95% of caffeine and many drugs. rs762551 sits in intron 1 near regulatory sequence and is thought to influence how strongly the gene is induced rather than the enzyme's intrinsic shape, which is why environmental inducers like smoking and diet interact with the genotype.

A single regulatory SNP whose real-world impact is small next to how much coffee you drink, smoking, medicines and other genes: don't treat 'fast/slow' as a fixed personal verdict.

What this isn’t: Not a medical test, not a heart-disease predictor, and not a basis for changing caffeine intake on health grounds.

dbSNP: rs762551 · Functional SNP rs762551 in CYP1A2 and coffee intake (ScienceDirect)

CCR5 CCR5Δ32: the HIV-resistance deletion (read via a proxy SNP) No Δ32 tag: deletion unlikely Established biology · inferred call

The famous 32-base deletion that, in two copies, makes most HIV-1 unable to enter your cells: the genotype behind the 'Berlin' and 'London' patients. We can't type the deletion itself, so we read a nearby tag SNP that travels with it in people of European descent. That makes this an inference, not a direct readout.

Your genotype: G/G (Immunity & infection)
Most-associated reading: No Δ32 tag: deletion unlikely

You don't carry the tag allele, so you most likely don't carry Δ32: the common result. A caveat that cuts the other way: in non-European ancestry the tag and the deletion aren't reliably linked, so 'no tag' there is genuinely uninformative rather than reassuring.

How seriously to take this: the evidence

Strength: Established biology · inferred call
Source of the claim: PubMed / GWAS: CCR5Δ32 (rs333) as HIV-1 co-receptor knockout; rs113341849 used as its r²≈0.97 tag SNP where the deletion can't be genotyped directly.
Effect: CCR5 is the main co-receptor R5-tropic HIV-1 uses to enter cells. Δ32 truncates the protein so it never reaches the surface. Δ32/Δ32 people are strongly resistant to R5-tropic HIV-1; Δ32/+ people who do get infected tend to progress more slowly. The biology here is solid: what's soft is that we infer your Δ32 status from a proxy SNP rather than reading the deletion.

The CCR5 protein sits on immune-cell surfaces and is the doorway most HIV-1 strains use. The Δ32 allele deletes 32 bases, frame-shifting the gene so no working receptor is made. With two copies there is essentially no doorway, so R5-tropic HIV-1 can't get in. rs113341849 sits nearby and is inherited together with Δ32 in European-descent populations, so its A allele stands in for the deletion we can't directly see.

This is a PROXY, not the deletion: the tag travels with Δ32 about 97% of the time in Europeans, and that link is weak-to-meaningless in non-European ancestry. There, a 'no tag' result tells you little. Resistance is also not immunity: X4-tropic HIV-1 strains can still infect Δ32/Δ32 people, and one Δ32 copy is NOT protection from getting HIV. Nothing here is medical advice. Do not change how you protect yourself from HIV based on this card.

What this isn’t: Not a direct test for the deletion, not immunity, not a clinical result, and not a reason to alter prevention. Δ32/Δ32 also carries a downside: links to worse symptomatic West Nile virus and possibly more severe influenza, so 'resistance allele' doesn't mean 'better immune system'. (This is the gene the 2018 CRISPR-baby experiment targeted; editing it in healthy embryos was condemned worldwide.)

MedlinePlus Genetics: CCR5 gene · SNPedia: rs333 (CCR5-Δ32) · dbSNP: rs113341849 (tag SNP)

CLOCK CLOCK: chronotype (morningness / eveningness) One evening-associated allele Preliminary

A core circadian-clock gene. The 3111T/C variant has been linked, inconsistently, to a tendency toward eveningness and later sleep timing.

Your genotype: A/G (Sleep & chronotype)
Most-associated reading: One evening-associated allele

One copy of the evening-associated allele: a small, inconsistent nudge toward later timing at most.

How seriously to take this: the evidence

Strength: Preliminary
Source of the claim: PubMed: circadian-genetics studies (mixed replication)
Effect: The evening-associated allele has been linked in some cohorts to greater eveningness and delayed sleep timing, but replication is patchy and effect sizes are small.

CLOCK encodes a core transcription factor of the circadian oscillator. rs1801260 lies in the 3' UTR and may subtly affect transcript regulation and clock period.

Chronotype is highly polygenic (dozens of loci) and strongly shaped by light exposure, age and behaviour; this single variant captures only a sliver and is among the weaker reported associations.

What this isn’t: Not a diagnosis of a sleep disorder and not a fixed verdict on when you must sleep.

GeneCards: CLOCK gene · dbSNP: rs1801260

COL5A1 Tendon stiffness & flexibility (COL5A1) Greater flexibility, lower risk Mixed evidence

A collagen variant linked, modestly, to how stiff or supple your tendons and ligaments tend to be, and a small tilt in soft-tissue injury risk and range of motion. The signal is real but population-dependent and easily swamped by training.

Your genotype: C/C (Fitness & performance)
Most-associated reading: Greater flexibility, lower risk

Two protective copies: the genotype some studies link to greater joint range of motion and the lowest reported soft-tissue injury risk. The effect is small.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: Collagen soft-tissue / tendon-injury candidate-gene literature, meta-analysed: modest signal in Caucasian cohorts, doesn't replicate in Asian ones
Effect: Some studies associate the TT genotype with a modestly higher risk of musculoskeletal soft-tissue injuries (tendon/ligament) and reduced joint flexibility, with the C allele appearing protective and linked to greater range of motion. The effect is small, population-dependent, and does not replicate everywhere: a wellness-curiosity signal, not a clinical injury predictor.

COL5A1 encodes the alpha-1 chain of type V collagen, which regulates the assembly and diameter of type I collagen fibrils in tendons and ligaments. rs12722 sits in the 3' untranslated region and is thought to influence mRNA stability/expression; the T variant is proposed to shift the collagen ratio toward thinner, less tensile-strong fibrils.

Load management, warm-up, biomechanics and training history drive injury risk far more than this single variant, and the association is inconsistent across populations.

What this isn’t: Not a talent test and not a diagnosis of injury-proneness.

dbSNP: rs12722 · COL5A1 rs12722 and soft-tissue injuries: meta-analysis (PMC5880610)

COMT COMT: dopamine clearance ('warrior / worrier') Worrier (slower clearance) Mixed evidence

How quickly your prefrontal cortex clears dopamine. The Val158Met variant tilts the dial between steady focus under pressure and flexible, exploratory thinking.

Your genotype: A/A (Cognition & stress)
Most-associated reading: Worrier (slower clearance)

Two Met alleles: slower clearance and higher tonic prefrontal dopamine, associated on average with better working memory in calm conditions but more dopamine 'overflow' and reactivity under stress.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: PubMed: multiple cognitive-genetics cohorts
Effect: The Met (A) allele lowers COMT enzyme activity, so prefrontal dopamine lingers longer; the Val (G) allele clears it faster. Average group differences in working memory and stress reactivity are real but small and easily swamped by sleep, training and context.

COMT breaks down synaptic dopamine. Val158Met (rs4680) changes the enzyme's thermostability, so Met/Met carriers have roughly 3–4× lower activity and higher tonic prefrontal dopamine than Val/Val carriers.

The 'warrior/worrier' story is a popular simplification of a U-shaped, task- and stress-dependent effect: neither genotype is 'better', and a single SNP explains only a sliver of the variance.

What this isn’t: Not a measure of intelligence or resilience, and not a prediction of your response to any medication: discuss stimulants or psychiatric medicines only with a prescriber.

MedlinePlus Genetics: COMT gene · dbSNP: rs4680

ANKK1 DRD2 / ANKK1: Taq1A, dopamine reward signalling A1 carrier Mixed evidence

The Taq1A variant beside the dopamine D2-receptor gene, long studied for differences in reward learning, motivation and addiction vulnerability.

Your genotype: G/A (Cognition & stress)
Most-associated reading: A1 carrier

One A1 allele: associated on average with somewhat lower D2-receptor availability; the behavioural differences reported are small.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: PubMed: neuroimaging & behavioural-genetics cohorts
Effect: The A1 (A) allele is associated on average with lower striatal D2-receptor density and subtle differences in reward sensitivity and reinforcement learning. The link to addiction is real but weak and heavily modified by environment.

rs1800497 (Taq1A) is a missense variant in ANKK1, immediately adjacent to DRD2; A1 carriers show reduced striatal D2-receptor availability on PET imaging, shifting dopaminergic reward signalling.

Early 'reward deficiency' claims were overstated; effect sizes are small and addiction risk is overwhelmingly driven by environment, not this SNP.

What this isn’t: Not a predictor of addiction, willpower or any disorder: it is one small dopaminergic modifier among many.

MedlinePlus Genetics: DRD2 gene · dbSNP: rs1800497

DRD4 Novelty-seeking, the contested version (DRD4) Common genotype: tells you little Contested

A dopamine-receptor promoter variant often tied to novelty-seeking or 'the wanderlust gene': included as a contested entry. The personality fame really rests on a repeat in the gene that we cannot type, and the SNP associations are small and inconsistent. It tells you very little.

Your genotype: T/T (Social & personality)
Most-associated reading: Common genotype: tells you little

Ordinary variation that implies nothing reliable about your personality or behaviour.

How seriously to take this: the evidence

Strength: Contested
Source of the claim: DRD4 promoter SNP; meta-analyses find at most a small, inconsistently replicated novelty-seeking/ADHD association, and the famous signal is the exon-3 48bp VNTR (7R), not this SNP
Effect: This SNP tells you very little. The novelty-seeking, extraversion and ADHD associations attached to rs1800955 are small, disputed and frequently fail to replicate; functional studies have even questioned whether it meaningfully changes DRD4 transcription. Any single-SNP 'personality readout' framing is oversold.

rs1800955 sits in the DRD4 promoter (~521 bp upstream of the start), where it could in principle nudge gene expression, though direct transcriptional effects have been hard to confirm. The famous DRD4 'novelty-seeking' signal comes from the exon-3 48bp VNTR (the 7R repeat allele): a separate length polymorphism, NOT this SNP, and not inferable from it.

Personality is not genetic destiny: traits like curiosity or impulsivity arise from environment, life experience and the combined tiny effects of very many genes, not one promoter SNP. Don't use this to label yourself or anyone, diagnose ADHD, or predict temperament.

What this isn’t: Explicitly NOT a novelty-seeking, 'adventure gene', impulsivity or ADHD diagnostic test, and not a personality assessment.

dbSNP: rs1800955 · No direct effect of the -521 C/T polymorphism on DRD4 transcription (PMC1481588)

FAAH Anandamide tone (FAAH) Standard FAAH activity Mixed evidence

A variant in the enzyme that breaks down anandamide: one of the body's own cannabis-like signalling molecules. Carriers of the low-activity allele have higher anandamide tone, loosely tied to differences in anxiety, reward and pain. The molecular effect is solid; the behavioural read-out is noisy.

Your genotype: C/C (Cognition & stress)
Most-associated reading: Standard FAAH activity

Two Pro129 copies: full enzyme activity and typical anandamide turnover. The most common genotype, treated as the behavioural baseline.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: Functional biochemistry (enzyme stability) is solid; the behavioural associations come from many small-to-moderate human studies with conflicting directions
Effect: The minor (A) allele lowers the enzyme's activity, so A-carriers tend to have higher anandamide levels, and studies have loosely linked this to differences in anxiety, fear-extinction, reward and pain. The psychological signal is real-but-noisy: present in some cohorts, absent or reversed in others.

FAAH degrades anandamide and related fatty-acid amides that act on cannabinoid receptors. The Pro129Thr change makes the enzyme more prone to degradation, shortening its half-life and raising steady-state anandamide. Higher anandamide tone is the proposed route to altered threat processing and reward signalling.

Effect sizes for anxiety/well-being/pain are small and frequently fail to replicate. This is NOT the dramatic 'no fear, no pain' phenotype of the rare FAAH-OUT case (Jo Cameron), which involved additional mutations.

What this isn’t: Not a pain-immunity, fearlessness or 'happiness' gene, and not a clinical or psychiatric diagnosis.

dbSNP: rs324420 · FAAH rs324420: biological pathways review (PMC10606937)

FADS1 Omega-3/6 conversion efficiency (FADS1) Efficient plant-to-long-chain conversion Replicated · small effect

How readily your body upgrades plant-form omega-3 and omega-6 fats into the long-chain forms (EPA, arachidonic acid) the body actually uses. One of the most reproducible nutrition-genetics signals, though what you eat matters far more than your genotype.

Your genotype: G/G (Nutrition & metabolism)
Most-associated reading: Efficient plant-to-long-chain conversion

Tends toward the most efficient FADS1 activity: plant ALA/LA are converted to EPA/arachidonic acid relatively well, so blood long-chain omega levels tend to run higher from the same intake.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS Catalog + multiple PUFA GWAS/meta-analyses (InCHIANTI and others): one of the most reproducible nutrigenetic loci, modest per-person effect
Effect: People carrying the G allele tend to convert dietary plant omega-3 (ALA) and omega-6 (LA) into the long-chain forms (EPA, arachidonic acid) more readily, so they show higher blood levels from the same diet. T-allele carriers convert less efficiently, with TT individuals showing roughly 30-40% lower arachidonic acid/EPA in some studies. This is a tendency in conversion efficiency, not a guarantee of any particular blood level.

rs174537 tags variation that affects FADS1 expression (the T allele is linked to increased promoter methylation and lower FADS1 protein). FADS1 encodes the Δ5-desaturase, a rate-limiting step turning precursor PUFAs into long-chain EPA and arachidonic acid. Lower activity means more reliance on preformed EPA/DHA from diet, such as oily fish.

Actual omega-3/6 status is driven mostly by what you eat: oily fish and direct EPA/DHA largely bypass this conversion step. The genotype shifts a tendency, it does not set your fatty-acid levels.

What this isn’t: Not a blood fatty-acid measurement and not a diagnosis of omega-3 deficiency.

dbSNP: rs174537 · GWAS of plasma PUFAs (InCHIANTI), PLoS Genetics

FKBP5 Stress-axis regulation, contested (FKBP5) Commonly studied genotype: no clear meaning Contested

A variant in a gene that tunes the body's stress-hormone feedback loop, studied for an interaction between childhood adversity and later PTSD or depression. The mechanism is plausible but the gene-by-environment evidence is contested: this is a research hypothesis, never a test.

Your genotype: T/T (Cognition & stress)
Most-associated reading: Commonly studied genotype: no clear meaning

Carries the genotype most often discussed in interaction studies, but on its own it tells you nothing about your stress resilience or mental health; the proposed effect only appears (weakly, inconsistently) alongside major adversity.

How seriously to take this: the evidence

Strength: Contested
Source of the claim: Candidate-gene / gene-by-environment stress-biology literature (Klengel/Binder group and follow-ups); GxE psychiatry has a poor replication record overall
Effect: Some studies report that, among people who experienced significant childhood adversity, T-allele carriers show modestly altered stress-hormone (cortisol/glucocorticoid) regulation and a somewhat higher reported rate of PTSD or depressive symptoms, but only in interaction with environment, never as a standalone effect. The associations are small, the literature is mixed, and several independent replications have been weak or null.

FKBP5 encodes a co-chaperone that regulates glucocorticoid-receptor sensitivity, part of the negative-feedback loop on the stress (HPA-axis) response. rs1360780 is an intronic variant proposed to act allele-specifically: in T-carriers, early-life trauma is reported to drive demethylation of an FKBP5 regulatory region. This is a proposed epigenetic-interaction mechanism, not a proven deterministic switch.

NOT a PTSD or depression test, and it cannot tell you whether you will experience either. Mental health is shaped by thousands of variants plus environment, relationships and chance; the gene-environment claim here is weak, debated and unreliable for any individual prediction.

What this isn’t: Not a psychiatric diagnosis and not a prediction that you will develop any mental-health condition.

Klengel et al. 2013, Nat Neurosci: FKBP5 demethylation mediates gene–childhood-trauma interaction · Border et al. 2019, Am J Psychiatry: no support for historical candidate-gene/GxE hypotheses for depression

FTO FTO: appetite & body-weight set-point Lower-risk genotype Replicated · small effect

The most-replicated common obesity-associated gene. The effect is genuine but small, and works mostly through appetite and satiety rather than metabolism.

Your genotype: T/T (Metabolism & appetite)
Most-associated reading: Lower-risk genotype

No copies of the risk allele: the lower end of this gene's small effect on appetite and weight.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS Catalog: large obesity meta-analyses
Effect: Each risk (A) allele is associated on average with roughly 1–1.5 kg higher body weight and somewhat reduced satiety. It is robustly replicated but explains only a tiny fraction of body-weight variance.

FTO risk variants act largely in the brain on appetite-regulating circuits (and on nearby genes such as IRX3/IRX5), nudging satiety and energy intake rather than basal metabolic rate.

The per-allele effect is small and fully modifiable: physical activity measurably blunts the FTO association, and diet and environment dominate the outcome.

What this isn’t: Not a diagnosis of obesity and not destiny: it shifts a probability slightly, nothing more.

MedlinePlus Genetics: FTO gene · GWAS Catalog: rs9939609

IGF2BP2 IGF2BP2: a lead type 2 diabetes marker typical Replicated · small effect

One of the first and most reproducible common variants linked to type 2 diabetes risk. It nudges the odds by a little; type 2 diabetes is highly polygenic and dominated by weight, diet and activity.

Your genotype: G/G (Metabolism & appetite)
Most-associated reading: typical

You don't carry the T allele at this marker. You can still develop type 2 diabetes: most of the risk is other genes and lifestyle.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS (NHGRI-EBI GWAS Catalog): among the earliest and most-replicated type 2 diabetes loci (2007 onward)
Effect: Each copy of the T allele at rs4402960 is associated with modestly higher odds of type 2 diabetes: a per-allele odds ratio of roughly 1.1 across large studies. It is one of dozens of common variants that each shift the odds only slightly.

rs4402960 lies in an intron of IGF2BP2, a gene in the insulin-like growth factor pathway that is active in pancreatic beta-cell development. The variant is thought to subtly affect insulin secretion rather than insulin resistance.

A real but small per-allele effect. Type 2 diabetes is highly polygenic and strongly shaped by weight, diet, activity and age: this single marker barely moves any one person's risk, and it is already one of the markers inside our polygenic type-2-diabetes score.

What this isn’t: Not a diagnosis of diabetes or pre-diabetes, and not a prediction that you will or won't develop it.

NHGRI-EBI GWAS Catalog: rs4402960 (type 2 diabetes) · dbSNP: rs4402960

CETP HDL & longevity curio (CETP I405V) Val/Val: higher-HDL longevity-linked form Mixed evidence

A cholesterol-transfer variant linked, in some long-lived families, to higher 'good' HDL cholesterol, larger lipoprotein particles and slower memory decline. The longevity story is real but inconsistent across populations: interesting, not a verdict on how long you'll live.

Your genotype: G/G (Aging & longevity)
Most-associated reading: Val/Val: higher-HDL longevity-linked form

The genotype enriched in Ashkenazi centenarian studies: associated there with larger HDL particles and slower memory decline. The effect is modest and population-dependent.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: Directly genotyped coding SNP; Ashkenazi centenarian/offspring cohorts (Barzilai lineage) plus other studies: real but population-heterogeneous
Effect: In several cohorts the Val/Val (G/G) genotype is associated with higher HDL cholesterol, larger HDL/LDL particles, and, in Ashkenazi Jewish centenarian families, exceptional longevity and slower memory decline versus Ile/Ile. These are population-specific, modest-effect associations that have not held up uniformly elsewhere (the direction even flips in some East-Asian samples), so any single result is easily over-sold.

CETP shuttles cholesteryl esters from HDL to other lipoproteins; the Val405 form is linked to lower CETP activity, which lets HDL accumulate as larger, cholesterol-rich particles. Larger lipoprotein particle size is the proposed link to favourable cardiovascular and cognitive ageing, but the amino-acid change is predicted benign, so any effect is subtle and indirect.

Longevity is overwhelmingly driven by lifestyle, environment and chance; this one SNP explains only a sliver of the variance, and its direction even flips between ancestries.

What this isn’t: Not a lifespan prediction and not a verdict on how long someone will live.

dbSNP: rs5882 · CETP I405V and memory decline / dementia (Sanders et al., PMC3047443)

FOXO3 Longevity-associated FOXO3 variant Two longevity-associated alleles Replicated · small effect

FOXO3 is one of only a couple of genes repeatedly linked to reaching very old age across many populations. A common variant is associated with slightly better odds of exceptional longevity, but lifestyle and luck dominate by far.

Your genotype: G/G (Aging & longevity)
Most-associated reading: Two longevity-associated alleles

You carry two copies of the G allele linked across populations to modestly higher odds of exceptional age. The reported effect is small and emerges only across large groups, not for any individual.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS and candidate-gene studies, Willcox et al. 2008, PNAS (Honolulu cohort); replicated in German, Italian, Chinese and other long-lived cohorts
Effect: The G allele at this site, which is the GRCh38 reference base, is the longevity-associated allele. People with two copies (the G/G genotype) showed modestly higher odds of reaching very old age than carriers of the T allele. Per-allele effects on lifespan are small and emerge only at the population level.

FOXO3 is a transcription factor in insulin and stress-response pathways linked to cellular maintenance; the variant is thought to subtly increase protective FOXO3 activity, though the exact functional change is still studied.

One of the better-replicated longevity signals, yet exceptional age is overwhelmingly shaped by environment, behaviour, chance and many other genes. This single marker barely moves any one person's odds.

What this isn’t: Not a prediction of your lifespan, not a health diagnosis, and not a reason to change anything you do.

Willcox et al. 2008, PNAS, FOXO3 and human longevity (PMID 18765803) · dbSNP, rs2802292

KL Klotho KL-VS: heterozygote-advantage curio KL-VS non-carrier (baseline) Contested

An unusual longevity/cognition variant where carrying exactly ONE copy (not two) is the form linked to better outcomes in some studies. The signal is genuinely contested: it fails to replicate in several large cohorts, so read it as a research curiosity, not a benefit.

Your genotype: T/T (Aging & longevity)
Most-associated reading: KL-VS non-carrier (baseline)

The most common, reference comparison group: without the heterozygote-associated advantages reported in some studies.

How seriously to take this: the evidence

Strength: Contested
Source of the claim: Directly genotyped coding SNP used as a KL-VS haplotype tag; positive cohorts + meta-analyses, but large non-replications (Newcastle 85+, UK Biobank)
Effect: KL-VS heterozygotes (one copy) have, in several studies, shown better cognition, higher circulating klotho, and a longevity edge at older ages, while non-carriers and, importantly, homozygous-variant individuals do worse. It is a balanced, heterozygote-advantage pattern, NOT a dose response, and it does not replicate in all cohorts, so it is easy to over-sell.

The Val352 substitution alters klotho protein trafficking/secretion: heterozygotes show increased secreted klotho whereas homozygous KL-VS carriers paradoxically show reduced klotho: a plausible basis for one copy being optimal. Klotho influences FGF23/phosphate, insulin/IGF-1 and oxidative-stress pathways, the proposed routes to its effects.

Lifespan and cognitive ageing are dominated by environment, lifestyle and chance; this single haplotype explains very little and its longevity association fails to replicate in major cohorts. rs9536314 alone only infers KL-VS status.

What this isn’t: Not a lifespan prediction and not a longevity verdict.

dbSNP: rs9536314 · No KLOTHO–longevity association in Newcastle 85+ and UK Biobank (PMC8893196)

MAOA The 'warrior gene' myth (MAOA) Common genotype: says essentially nothing Popularly over-hyped

The notorious 'warrior gene': included to set the record straight, not to label anyone. The headline story rests on a repeat in the gene's promoter that we cannot read, and the aggression narrative is badly oversold and has a real history of misuse. This SNP says essentially nothing about you.

Your genotype: G/G (Social & personality)
Most-associated reading: Common genotype: says essentially nothing

This result carries no meaningful behavioural implication and should be read as ordinary human variation, not a trait. (On the X chromosome, this is the common single/double-copy state.)

How seriously to take this: the evidence

Strength: Popularly over-hyped
Source of the claim: A synonymous MAOA tag SNP repeatedly press-styled as a 'warrior gene' readout; the fame actually attaches to the MAOA promoter uVNTR (3R/4R), a tandem repeat we cannot type
Effect: This SNP says very little about you. Reported links between rs6323 and aggression, ADHD or psychiatric traits are weak, frequently non-replicated, and confounded by population structure and study design; the popular 'warrior gene' story is badly oversold relative to the evidence. At most this is a faint, indirect proxy that should never be read as a behavioural prediction.

rs6323 is a synonymous change at codon 297 (arginine either way), so it does not alter the MAOA protein; any influence would be regulatory or via weak linkage. Critically, the headline MAOA promoter VNTR (the famous 3-repeat vs 4-repeat "uVNTR") is a separate, length-based polymorphism: it is NOT this SNP and is not captured by it. MAOA is on the X chromosome, so males carry a single copy.

Behaviour is not genetic destiny: aggression and personality are overwhelmingly shaped by environment, upbringing and the combined tiny effects of many genes: there is no single 'violence gene'. This locus has a documented history of misuse, including ethnic stereotyping and courtroom misapplication, and must never be used to label, predict or judge anyone.

What this isn’t: Explicitly NOT a 'warrior gene', aggression, violence or criminality test, and not a personality or psychiatric diagnosis.

dbSNP: rs6323 · Chasing the 'warrior gene': why it looks like a dud (Genetic Literacy Project)

WWC1 KIBRA memory-performance variant (WWC1) Reference Mixed evidence

An intronic variant in the WWC1 (KIBRA) gene was an early, much-discussed hit for episodic memory: carriers of one allele recalled slightly more in some studies. Later work has been inconsistent, so this is an emerging, contested association rather than a settled one.

Your genotype: C/C (Cognition & memory)
Most-associated reading: Reference

You carry two reference alleles, not carrying the recall-associated T allele at this marker. Plenty of strong rememberers are C/C.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: GWAS and candidate-gene studies, Papassotiropoulos et al. 2006, Science; later meta-analysis (Milnik et al. 2012) with mixed results
Effect: T-allele carriers (C/T or T/T) were reported in the original and several follow-up studies to outperform C/C individuals on delayed episodic-recall tasks. A 2012 meta-analysis found the effect smaller and less consistent than first reported.

WWC1 encodes KIBRA, a protein involved in synaptic plasticity and memory formation in the hippocampus; the variant is intronic and any functional effect on memory is indirect and not fully mapped.

A genuinely famous early finding that has not replicated cleanly. Memory is highly polygenic and shaped by sleep, age, education and practice; this single marker explains very little.

What this isn’t: Not a diagnosis, not a dementia test, and not a measure of your intelligence or memory ceiling.

Papassotiropoulos et al. 2006, Science, KIBRA and human memory (PMID 17053149) · dbSNP, rs17070145

MTHFR MTHFR: C677T, the most over-hyped variant in consumer genetics C/T (mildly reduced) Popularly over-hyped

You have almost certainly been told MTHFR matters. Here is the plain version: for the vast majority of people it does not, which is exactly why our clinical module does NOT report it.

Your genotype: G/A (Metabolism & appetite)
Most-associated reading: C/T (mildly reduced)

One 677T allele: about 65% of typical enzyme activity, with no health implication at normal folate intake. Extremely common.

How seriously to take this: the evidence

Strength: Popularly over-hyped
Source of the claim: ACMG practice guidance; MedlinePlus Genetics
Effect: The 677T (A) allele modestly lowers MTHFR enzyme activity. T/T can raise homocysteine slightly when folate intake is low: an effect that essentially disappears with normal folate status.

MTHFR helps convert folate into its active form for homocysteine metabolism. C677T (rs1801133) reduces the enzyme's thermostability, lowering activity to about 65% (C/T) or 30% (T/T) of normal, but adequate dietary folate compensates.

Major bodies, including the ACMG, advise AGAINST testing MTHFR for thrombophilia or recurrent pregnancy loss: the evidence does not support the elaborate claims sold around it. We surface it here only to set the record straight.

What this isn’t: NOT a cause of your symptoms, not a reason for special supplements without medical advice, and not a clinical finding: it is a normal, common variant.

MedlinePlus Genetics: MTHFR gene · ACMG practice guideline: lack of evidence for MTHFR testing (PubMed)

MTNR1B Glucose & melatonin crossover (MTNR1B) Baseline glucose-circadian profile Replicated · small effect

A common variant in a melatonin receptor that nudges fasting blood sugar slightly upward, and sits at an unusual crossover where melatonin and late-night eating affect glucose handling more in carriers. A small statistical tilt, not a verdict.

Your genotype: C/C (Metabolism & appetite)
Most-associated reading: Baseline glucose-circadian profile

No added risk-allele copies: a typical fasting-glucose tendency and a typical melatonin-related glucose response, on average.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS Catalog + large European meta-analyses and Asian replication cohorts: robustly replicated, small per-allele effect
Effect: Carrying the G allele is associated, on average, with very slightly higher fasting blood-glucose readings and a small nudge in long-term type-2-diabetes risk-factor profiles: a tiny statistical tilt, not a switch. MTNR1B also sits at a melatonin/circadian crossover: in carriers, melatonin (including evening doses, or melatonin-disrupting late eating and shift schedules) appears to blunt glucose handling more than in non-carriers, which is why sleep and meal timing are part of this variant's story.

The melatonin receptor MTNR1B is expressed in pancreatic beta cells; the G allele is linked to higher receptor expression and reduced glucose-stimulated insulin release, especially overnight when melatonin is high. The net effect is slightly lower early insulin output and modestly higher fasting glucose, and a genotype that interacts with melatonin exposure.

A common, low-effect-size variant: the per-copy change in glucose is small and population-averaged. Diet, weight, activity, sleep, age and many other genes dominate the actual outcome.

What this isn’t: Not a diabetes diagnosis, not a prediction you will develop diabetes, and not a reason to start or stop melatonin without a clinician.

dbSNP: rs10830963 · MTNR1B G-allele and impaired fasting glycemia / T2D (PubMed 19324940)

CHRNA5 Nicotine dependence signal (CHRNA5) Common baseline form Replicated · small effect

A nicotinic-receptor variant that, among people who smoke, nudges the odds of smoking more heavily and finding it harder to quit. It is one of the most reliably replicated common variants in smoking genetics, and still only a small, probabilistic nudge per person.

Your genotype: G/G (Substance response)
Most-associated reading: Common baseline form

Two copies of the Asp398 allele: the typical genotype, with the population-average (lower) level of nicotine-dependence signal at this gene.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: Candidate-gene + genome-wide association studies of nicotine dependence / cigarettes-per-day, with many independent replications and functional cell-line work
Effect: Carrying the A (Asn398) allele is associated, on average, with somewhat heavier smoking and a higher likelihood of nicotine dependence among people who smoke; the effect is graded (one copy less than two). It is also linked to lung-cancer risk, but largely indirectly: through heavier and longer smoking, not as an independent cancer switch. The effect sizes are population-level averages and small for any one individual.

The variant changes amino acid 398 (Asp to Asn) in the alpha-5 subunit of neuronal nicotinic acetylcholine receptors. The Asn398 form shows altered receptor function: reduced response to agonist and changes in calcium signalling and desensitisation: plausibly blunting the early aversive effects of nicotine and shifting reward and habit dynamics.

A probabilistic risk modifier, not a verdict: most of whether and how much someone smokes is driven by environment, social context and other genes, and many A-allele carriers never smoke or smoke lightly.

What this isn’t: It does not mean a person is destined to smoke, become dependent, or get lung cancer, and it is not a diagnosis.

dbSNP: rs16969968 · The CHRNA5-A3-B4 gene cluster and smoking (review, PMC5152594)

OPRM1 Mu-opioid receptor variant (OPRM1 A118G) Common Asn40 form Contested

A much-studied change in the brain's main opioid receptor that was once thought to shape pain, reward and how people respond to opioids, naltrexone and alcohol. It is included precisely as a cautionary tale: the early excitement has not held up.

Your genotype: A/A (Substance response)
Most-associated reading: Common Asn40 form

Two copies of the ancestral c.118A allele: the most common genotype in many populations, and the reference background against which the disputed associations were measured.

How seriously to take this: the evidence

Strength: Contested
Source of the claim: Candidate-gene pharmacogenetic studies and clinical-trial secondary analyses, followed by meta-analyses that largely temper the early findings
Effect: Some studies suggested G-allele carriers might respond differently to naltrexone or have altered pain, opioid and alcohol-reward responses, but rigorous meta-analyses find the effects small, inconsistent and often non-significant after correcting for multiple testing. Any association is weak and unreliable at the individual level. The right register here is curiosity, not prediction. Allele frequency varies widely by ancestry (much higher in East-Asian-ancestry populations).

The variant changes amino acid 40 (Asn to Asp) in the mu-opioid receptor and removes a putative N-glycosylation site. Proposed effects on receptor expression and binding exist, but the functional consequences in humans remain debated and not cleanly established.

One of the most famous 'promising then deflated' pharmacogenetic variants: it must not be used to choose, dose or predict response to any medication. Those decisions belong with a prescriber.

What this isn’t: It does not reliably predict how a person will respond to opioids, naltrexone or alcohol, and it is not a basis for any treatment decision.

dbSNP: rs1799971 · Meta-analysis: OPRM1 rs1799971 moderating naltrexone response in AUD (PMC7340566)

OXTR OXTR: rs53576, the oxytocin receptor & social behaviour G/G (early-study 'prosocial') Contested

A famous (and famously contested) variant in the oxytocin-receptor gene, popularly tied to empathy and sociality. We include it precisely to show how shaky 'social genetics' can be.

Your genotype: G/G (Social & personality)
Most-associated reading: G/G (early-study 'prosocial')

Two G alleles: the genotype early studies (weakly, and often non-replicated) tied to higher self-reported empathy and resilience.

How seriously to take this: the evidence

Strength: Contested
Source of the claim: PubMed: social-genetics studies (replication disputed)
Effect: Early studies linked the G allele to higher self-reported empathy, optimism and stress resilience. Large replication attempts have often failed, and the consensus is now sceptical.

OXTR encodes the oxytocin receptor, central to social bonding. rs53576 is intronic, so any functional effect is indirect and unproven: part of why the behavioural claims do not replicate well.

This is a cautionary tale: a single intronic SNP does not meaningfully determine personality, and most early 'candidate-gene' social findings have not held up. Treat any reading as entertainment.

What this isn’t: Not a measure of your empathy, kindness or social ability: behaviour here is overwhelmingly non-genetic.

dbSNP: rs53576 · Meta-analysis: a sociability gene? (OXTR rs53576, PubMed)

PPARGC1A PPARGC1A: Gly482Ser, endurance & mitochondria One Ser allele Mixed evidence

PGC-1alpha is the master regulator of mitochondrial biogenesis: the adaptation behind aerobic training. The Gly482Ser variant is studied for differences in endurance trainability.

Your genotype: C/T (Fitness & performance)
Most-associated reading: One Ser allele

One Ser allele: small, inconsistent average differences in endurance measures at most.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: PubMed: exercise-genomics cohorts
Effect: The Ser (T) allele has been associated in some studies with slightly lower endurance performance and trainability and with some metabolic traits, but results vary across cohorts.

PPARGC1A (PGC-1alpha) drives mitochondrial biogenesis and oxidative-fibre adaptation to aerobic exercise. Gly482Ser (rs8192678) may modestly affect the function of this transcriptional co-activator.

Athletic performance is massively polygenic and training-dominated; single-gene 'sports genetics' is mostly entertainment, and the effect sizes here are small and inconsistent.

What this isn’t: Not a ceiling on your fitness and not a basis for any training or talent decision.

GeneCards: PPARGC1A gene · dbSNP: rs8192678

FUT2 Secretor status: norovirus and B12 (FUT2) Secretor Replicated · small effect

Whether you are a 'secretor', meaning you display blood-group sugars in saliva, gut and other secretions. The common nonsecretor variant is associated with strong resistance to the most widespread strains of norovirus, and with somewhat higher vitamin B12 blood levels, because the same sugars that norovirus uses to attach are absent.

Your genotype: G/G (Immunity & infection)
Most-associated reading: Secretor

You carry two working copies and display the blood-group sugars in secretions. Most people are secretors and are susceptible to the common norovirus strains.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: Functional and association studies on secretor status, plus GWAS (NHGRI-EBI GWAS Catalog) for vitamin B12 and norovirus susceptibility
Effect: The A allele is a stop variant (Trp154Ter); two copies (A/A) make a nonsecretor, robustly associated with resistance to the dominant GII.4 norovirus strains and with higher blood vitamin B12. G/G and G/A are secretors and susceptible to those strains.

FUT2 builds the H-antigen sugars on gut and secretion surfaces. Most noroviruses dock onto those sugars to infect; nonsecretors lack them, so the common strains cannot attach. The same biology shifts how B12 is handled in the gut.

Resistance is strain-specific, not absolute: some rarer norovirus strains still infect nonsecretors. The B12 effect is a small population-level shift. Secretor status also relates to other gut and infection traits not described here.

What this isn’t: Not a guarantee against stomach bugs and not a diagnosis or a B12-deficiency test.

NHGRI-EBI GWAS Catalog, rs601338 · dbSNP, rs601338

ADRB1 Natural short sleeper: ADRB1 Typical sleep need (no short-sleep allele) Single study

A second, equally rare 'short sleeper' variant: carriers in one studied family felt rested on roughly four to six hours. As with the DEC2 version, nearly everyone is reference and has a normal sleep need; this is a curiosity, not a target.

Your genotype: C/C (Sleep & chronotype)
Most-associated reading: Typical sleep need (no short-sleep allele)

The reference genotype carried by nearly everyone: a normal, average sleep requirement, with no link to the ADRB1 short-sleep trait.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: Shi et al., Neuron 2019: one large family (FNSS2); confirmed by a CRISPR knock-in mouse
Effect: This extremely rare allele is associated with feeling rested on roughly four to six hours of sleep, less than the typical adult need. It was found in one multigenerational family and is exceedingly rare in population databases, so almost everyone is reference (C/C) with an ordinary sleep requirement. The human evidence is from a single pedigree and should be read as suggestive, not definitive for any individual.

ADRB1 encodes the beta-1 adrenergic receptor; the Ala187Val change sits in a conserved region and yields a less stable receptor with reduced signalling. In mice the variant makes neurons in a wake-promoting region of the dorsal pons more active, which is thought to shorten sleep while preserving daytime function.

A rare familial short-sleep trait carried by one studied family: NOT advice or permission to sleep less. For the non-carrier majority, cutting sleep produces real sleep deprivation and health costs.

What this isn’t: Not a common 'you can run on four hours' marker, and not a population-wide sleep-need dial.

dbSNP: rs776439595 · OMIM: Short sleep, familial natural, 2 (FNSS2, 618591)

BHLHE41 Natural short sleeper: DEC2 (BHLHE41) Typical sleep need (no short-sleep allele) Single study

The famous (and vanishingly rare) variant behind people who feel fully rested on about two hours less sleep than average. Almost everyone carries the reference version and has an ordinary sleep need: this is included as a curio, not a goal.

Your genotype: G/G (Sleep & chronotype)
Most-associated reading: Typical sleep need (no short-sleep allele)

The reference genotype carried by nearly everyone: an ordinary, average sleep requirement, with no link to the DEC2 short-sleep trait.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: He et al., Science 2009: the first human short-sleep mutation; reproduced in knock-in mice and flies
Effect: This extremely rare allele is linked to a lifelong tendency to feel fully rested on roughly two hours less sleep than average, without daytime impairment. It has been reported in only a handful of families worldwide, so essentially everyone is reference (G/G) here and has an ordinary sleep need. The association is real but rests on very small human samples, even though animal models recreate the trait.

DEC2/BHLHE41 is a transcriptional repressor in the circadian clock; the Pro384Arg change reduces its repressive activity. In model animals this raises arousal-promoting orexin (hypocretin) signalling in the hypothalamus, which is thought to compress sleep duration while preserving sleep quality.

Short sleep here is a rare inherited trait carried by a few families: it is NOT a license or an instruction to sleep less. For the reference (non-carrier) majority, deliberately curtailing sleep causes genuine sleep deprivation.

What this isn’t: Not a common 'sleep less and feel fine' switch you can flip, and not advice to shorten your sleep.

dbSNP: rs121912617 · ClinVar: BHLHE41 p.Pro384Arg, familial natural short sleep 1

SLC6A4 Serotonin transporter (5-HTTLPR): the famous null Common genotype: no actionable meaning Contested

The serotonin-transporter promoter: once the most famous 'depression-and-stress' result in all of behavioural genetics, and now the textbook example of a finding that didn't replicate. Included for exactly that reason: it has essentially no predictive value for any individual.

Your genotype: T/T (Cognition & stress)
Most-associated reading: Common genotype: no actionable meaning

The reference result at this position; given the failed replications it tells you nothing reliable about mood, stress response or depression risk.

How seriously to take this: the evidence

Strength: Contested
Source of the claim: Legacy candidate-gene literature (5-HTTLPR), now largely discredited for depression prediction; the 2003 stress-interaction failed large replication (Border et al. 2019)
Effect: Early studies proposed that serotonin-transporter promoter variation interacted with stressful life events to raise depression risk, and rs25531 was used to refine the classic long/short promoter calls. This famous interaction did NOT hold up: large well-powered studies and meta-analyses, culminating in Border et al. 2019 across hundreds of thousands of people, found no reliable association and no gene-by-environment effect. The plain reading is that this locus has essentially no demonstrated predictive value for depression in individuals.

SLC6A4 encodes the serotonin transporter (the SSRI target). rs25531 does not act alone: it tags and modifies the 5-HTTLPR, a roughly 43 bp insertion/deletion in the promoter (the 'long' vs 'short' allele), NOT a simple SNP. Because the real functional element is an indel that this SNP only partially indexes, a single-SNP read-out is inherently incomplete.

NOT a depression test, and it carries essentially no reliable predictive power for any individual; the large-replication evidence is that the historical claims were false positives. Mood and mental health are multi-factorial (polygenic, environmental and circumstantial) and this single position should not change how anyone thinks about their risk.

What this isn’t: Not a psychiatric diagnosis and not a prediction of depression or any mental-health outcome.

Border et al. 2019, Am J Psychiatry: the large-scale non-replication of 5-HTTLPR×stress · dbSNP: rs25531

TCF7L2 Glucose handling: the strongest common T2D variant (TCF7L2) Baseline / lower-risk genotype Replicated · small effect

The single most reproducible common-variant link to type-2-diabetes risk and how the body releases insulin. Even so, the per-copy effect is small and most carriers never develop diabetes: a risk-factor nudge weighed alongside lifestyle and family history.

Your genotype: C/C (Metabolism & appetite)
Most-associated reading: Baseline / lower-risk genotype

No T copies: a typical insulin-secretion profile and the lowest of the three average risk tilts at this locus.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS Catalog flagship signal + many large case-control studies and meta-analyses across ancestries: the most reproducible common T2D variant, modest per-allele effect
Effect: Carrying the T allele is associated, on average, with a somewhat higher long-term chance of impaired glucose handling and type-2 diabetes: the strongest common-variant tilt known for this trait, but per copy the effect is still small in absolute terms (odds ratio roughly 1.3-1.5). It nudges a risk-factor profile, not a fate; most T-allele carriers never develop diabetes.

TCF7L2 is a transcription factor in the Wnt signalling pathway; the T allele alters regulatory activity in pancreatic islets and is linked to impaired glucose-stimulated insulin secretion and a reduced incretin (GLP-1) effect. The result is a poorer first-phase insulin response: it mainly affects insulin output rather than insulin resistance.

Even as the strongest common T2D variant, the per-allele effect is modest and population-averaged; absolute risk for any individual stays low-to-moderate. Body weight, diet, activity, age, ancestry and many other variants dominate the real-world outcome.

What this isn’t: Not a diabetes diagnosis and not a prediction that you will become diabetic: only a probabilistic risk-factor marker.

dbSNP: rs7903146 · The Role of TCF7L2 in Type 2 Diabetes (ADA, Diabetes 2021)

CYP2R1 Vitamin-D tendency: activation enzyme (CYP2R1) Tends toward higher baseline vitamin D Replicated · small effect

A second vitamin-D tendency variant: this one in the liver enzyme that activates vitamin D into the measured form. A small, reproducible nudge that pairs with the GC binding-protein variant; sunlight and supplements still dominate.

Your genotype: A/A (Nutrition & metabolism)
Most-associated reading: Tends toward higher baseline vitamin D

Two copies of the favourable (reference) allele: associated with the highest average measured 25(OH)D and the most efficient activation tendency.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS Catalog / SUNLIGHT consortium large meta-analyses + replications: genome-wide significant and consistently replicated, small per-allele effect
Effect: Here the reference allele A is the favourable, higher-vitamin-D one and the common G allele is the risk allele. Each copy of the G allele is associated, on average, with modestly lower measured 25-hydroxyvitamin D and somewhat higher odds of insufficiency (roughly 1.2x per G allele in the discovery cohort). A small, reproducible nudge, not a determinant.

CYP2R1 encodes the main 25-hydroxylase that converts vitamin D into 25-hydroxyvitamin D in the liver: the form that blood tests measure. The G allele is linked to lower CYP2R1 activity/expression, so less precursor is hydroxylated into 25(OH)D, lowering the measured level.

Like the GC variant, real-world 25(OH)D is governed mostly by sun exposure, season, latitude, skin tone and supplementation; this genotype only shifts a baseline tendency.

What this isn’t: Not a vitamin-D blood test and not a diagnosis of vitamin-D deficiency.

dbSNP: rs10741657 · Common variants in CYP2R1 and GC predict vitamin D (PMC3937412)

GC Vitamin-D tendency: binding protein (GC) Tends toward higher baseline vitamin D Replicated · small effect

A nudge in how much vitamin D your blood tends to carry, via the main protein that ferries it around. A top, reproducible genetic signal for vitamin-D level, but sunlight, season and supplements move the needle far more.

Your genotype: T/T (Nutrition & metabolism)
Most-associated reading: Tends toward higher baseline vitamin D

The major-allele genotype: associated with the highest average circulating 25(OH)D of the three, before diet and sun are accounted for.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS Catalog / SUNLIGHT consortium large meta-analyses (tens of thousands of Europeans) + replications: highly consistent direction, small per-allele effect
Effect: Each copy of the G allele is associated, on average, with modestly lower measured 25-hydroxyvitamin D in the blood, and a higher likelihood of falling into the insufficient range in some cohorts. T-allele carriers tend to run a little higher. The effect is real and reproducible but small at the individual level.

GC encodes vitamin-D binding protein, which carries about 85-90% of circulating 25(OH)D in the blood. rs2282679 tags variants altering this binding protein (it is tightly linked to the rs4588/rs7041 protein isoforms), changing how much 25(OH)D is held in circulation and thus the total level that is measured.

Sunlight (UVB) exposure, latitude, season, skin tone and supplementation dominate actual vitamin-D status far more than this genotype. The variant nudges a baseline tendency.

What this isn’t: Not a vitamin-D blood test and not a diagnosis of vitamin-D deficiency.

dbSNP: rs2282679 · Common variants of GC and 25(OH)D (PMC3613945)

The Fringe

Speculative · for curiosity only

Read from your file: 1 of 22. The other 21 had no variant reported in your file, so they’re read as the common (reference) genotype — an inference, not a measurement (see each card’s note).

OR2M7 Asparagus pee: can you smell it? (OR2M7 cluster) Likely can't smell it Single study

Whether your genes tilt you toward being unable to smell the distinctive sulfurous odour in urine after eating asparagus. A variant in a dense cluster of smell-receptor genes shifts the odds; this is about perception, not anything about your health.

Your genotype: A/A (Taste & smell)
Most-associated reading: Likely can't smell it

You carry two copies of the allele linked to reduced ability to smell the asparagus urine odour. Some A/A people smell it just fine.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: GWAS, Pelchat et al. 2011, Chemical Senses, a psychophysical and genetic study of asparagus urine odour
Effect: The reference A allele was associated with reduced ability to smell the asparagus urine odour (asparagus anosmia). The G allele tracks the ability to smell it. The per-allele effect is modest.

The variant sits at the end of chromosome 1 inside a cluster of about fifty olfactory-receptor genes, nearest OR2M7; the cluster is thought to house the receptors for the sulfurous odour compounds.

A modest, single-study signal. Whether you notice the smell also depends on how much asparagus you ate and how recently, and most of the variation is other genes.

What this isn’t: Not a diagnosis and not a sign of any smell disorder; it is one quirk at one of many smell receptors.

Pelchat et al. 2011, Chemical Senses, asparagus urine odour (PMID 20876394) · dbSNP, rs4481887

TAS2R38 Bitter taste: PTC taster or not (TAS2R38) Bitter-sensitive (taster-leaning) Replicated · small effect

Whether your genes make you sensitive to certain bitter compounds (PTC and PROP) found in foods like brassicas, coffee and tonic water. This bitter-taste receptor is one of the best-studied taste genes; the marker below is its single best-characterised site.

Your genotype: C/C (Taste & smell)
Most-associated reading: Bitter-sensitive (taster-leaning)

You carry two copies of the reference allele tagging the taster form of the receptor; PTC-type bitterness tends to register strongly.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: Functional and association studies, Kim et al. 2003, Science, positional cloning of the PTC bitter-taste receptor
Effect: At this site the reference C allele (Pro49) and the G allele (Ala49) tag the two main TAS2R38 forms. The taster form tracks greater sensitivity to PTC and PROP bitterness; the non-taster form tracks reduced sensitivity. The full receptor is defined by three linked sites, of which this is the lead.

TAS2R38 encodes a bitter-taste receptor on the tongue; the amino-acid differences change how strongly the receptor responds to thiourea compounds like PTC and PROP.

A real, well-replicated effect, but bitter perception of real foods also depends on the other linked sites in this gene, on saliva and on tongue papilla density, plus habit. A single site only tags the haplotype.

What this isn’t: Not a diagnosis and not a verdict on what you should eat; it describes sensitivity to a narrow class of bitter compounds.

Kim et al. 2003, Science, PTC bitter-taste receptor (PMID 12595690) · dbSNP, rs713598

KITLG Blond vs darker hair (KITLG) Darker default Established biology · inferred call

A well-understood 'highlights' variant: the lighter allele tilts hair blonder and is one of the top contributors to classic Northern-European blondness. It's a probabilistic nudge layered on top of the bigger eye-and-hair-colour machinery.

Your genotype: T/T (Hair & appearance)
Most-associated reading: Darker default

Full enhancer activity: on average the darkest of the three genotypes for this locus's contribution.

How seriously to take this: the evidence

Strength: Established biology · inferred call
Source of the claim: GWAS Catalog (Sulem 2007 / Han 2008) + Guenther et al. 2014 (Nat Genet) functional enhancer mechanism: replicated, mechanistically demonstrated
Effect: The C allele tilts hair lighter/blonder, and sits among the top contributors to classic Northern-European blondness. It works as a probabilistic nudge layered on the bigger HERC2/OCA2 eye-and-hair-colour machinery, and is characterised in European-ancestry samples. Lighter: not a guarantee of blond.

rs12821256 lies ~350 kb upstream of KITLG (KIT ligand) inside a hair-follicle enhancer; the C allele weakens an LEF1 transcription-factor binding site, lowering enhancer activity and KITLG expression in the follicle. Less KIT-ligand signalling to melanocytes yields less melanin in the hair shaft (a lighter, blonder tone) without affecting skin or eyes the way broad pigment genes do.

Hair colour is strongly polygenic; this SNP is one modest-effect regulatory tweak, and both its frequency and calibrated effect are European-ancestry-specific.

What this isn’t: Not 'the blond gene': it does not by itself dictate hair colour or override the larger pigment-gene network.

dbSNP: rs12821256 · Guenther et al. 2014, Nat Genet: a molecular basis for classic blond hair in Europeans

OR6A2 Cilantro tastes like soap (OR6A2) Soap-leaning Single study

Whether your genes nudge you toward perceiving a soapy note in fresh coriander (cilantro). A variant in a cluster of smell-receptor genes shifts the odds a little, but exposure, cuisine and plain habit matter far more.

Your genotype: C/C (Taste & smell)
Most-associated reading: Soap-leaning

You carry two copies of the reference allele that tracks the soapy perception. Plenty of C/C people enjoy cilantro anyway.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: GWAS (23andMe research cohort), Eriksson et al. 2012, Flavour, a genome-wide association study of cilantro preference
Effect: The A allele was associated with slightly lower odds of reporting cilantro as soapy. The reference C allele therefore tracks the soapy perception. The effect is small and explains only a sliver of the trait.

The variant sits within a cluster of olfactory-receptor genes on chromosome 11; OR6A2, which binds several of the aldehydes that give coriander its aroma, is the proposed receptor behind the soapy note.

A small, single-cohort signal. Many people learn to enjoy cilantro with exposure regardless of genotype, and most of the variation is not this one marker.

What this isn’t: Not a diagnosis, not a verdict that you must dislike coriander, and not destiny in the kitchen.

Eriksson et al. 2012, Flavour, cilantro preference GWAS · dbSNP, rs72921001

TCHH Straight vs curly hair (TCHH) Curl-leaning baseline Replicated · small effect

A gentle pull on where your hair sits on the straight-wavy-curly spectrum. The derived allele leans toward straighter hair: a fun but modest nudge, and one mostly studied in European and west/central-Asian ancestry.

Your genotype: A/A (Hair & appearance)
Most-associated reading: Curl-leaning baseline

No straightening copies: on average more toward wavy/curly within European-ancestry samples.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS Catalog: Medland et al. 2009 (Am J Hum Genet, straight hair in Europeans), replicated in later hair-shape meta-analyses; modest, ancestry-limited effect
Effect: The derived T allele leans hair toward straight, with roughly a 2-fold odds shift in the original European samples: a fun but gentle pull, not a curl verdict. The signal is concentrated in European and west/central-Asian ancestry, where the T allele is common, and is far less informative elsewhere. Hair shape is a continuum, and this SNP only nudges where you sit on it.

rs11803731 is an A>T change in TCHH (trichohyalin), giving a Leu->Met substitution in a structural protein that cross-links the inner root sheath of the hair follicle. Altered trichohyalin is thought to change follicle mechanics and thereby the cross-sectional shape and curvature of the growing hair shaft.

Hair curl is polygenic (many loci, plus development and age), and this single European-derived variant captures only a small fraction; allele frequency and effect are ancestry-specific.

What this isn’t: Not a pan-population 'straight hair gene', and it says little about curl in non-European-ancestry hair.

dbSNP: rs11803731 · Medland et al. 2009, Am J Hum Genet: TCHH variants and straight hair in Europeans

ABCC11 Wet or dry earwax (ABCC11) Dry earwax Replicated · small effect

A single well-studied variant largely determines whether your earwax is wet or dry, and tracks the amount of underarm odour your glands produce. This is one of the cleanest single-gene human traits.

Your genotype: T/T (Body quirks)
Most-associated reading: Dry earwax

You carry two copies of the allele linked to dry, flaky earwax and fewer underarm odour precursors. Common in East Asian ancestry.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: Functional and association studies, Yoshiura et al. 2006, Nature Genetics, the SNP in ABCC11 determines earwax type
Effect: The T allele (Gly180Arg) tracks dry, flaky earwax and reduced underarm odour; the reference C allele tracks wet, sticky earwax and more odour. Unusually for a trait, this single variant explains most of the difference. The T allele is common in East Asia and rare in Africa.

ABCC11 is a membrane transporter active in the glands that secrete earwax and underarm sweat; the T allele reduces transporter function, yielding drier wax and fewer odour precursors.

A genuinely strong single-gene effect for earwax, but underarm odour also depends heavily on skin bacteria, washing and clothing, so the body-odour link is looser than the earwax link.

What this isn’t: Not a diagnosis and not a hygiene verdict; it simply describes a gland-secretion type.

Yoshiura et al. 2006, Nature Genetics, ABCC11 earwax (PMID 16444273) · dbSNP, rs17822931

HERC2 Blue or brown eyes (HERC2) Brown-leaning Replicated · small effect

A single regulatory variant near the OCA2 pigment gene is the strongest single predictor of blue versus brown eyes. It is not the whole story (several genes fine-tune the shade), but this one site does most of the work.

Your genotype: A/A (Appearance)
Most-associated reading: Brown-leaning

You carry two copies of the reference allele linked to brown eyes. Other pigment genes set the exact shade.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: Functional and association studies, Eiberg et al. 2008, Human Genetics; Sturm et al. 2008, the HERC2 blue-brown eye switch
Effect: The reference A allele tracks brown eyes; the G allele tracks blue. G/G individuals are usually blue-eyed, while one or two A alleles usually means brown or hazel. This single site is strongly predictive but not absolute.

The variant lies in an intron of HERC2 in a regulatory element controlling the neighbouring OCA2 pigment gene; the G allele reduces OCA2 expression and iris melanin, yielding lighter eyes.

Strongly predictive for the blue-brown axis, but green, hazel and intermediate shades depend on additional genes such as OCA2, TYR and SLC24A4, so the exact colour is polygenic.

What this isn’t: Not a diagnosis and not a paternity or ancestry test; it predicts a pigment tendency, not a guaranteed colour.

Eiberg et al. 2008, Human Genetics, HERC2 blue eye colour (PMID 18172690) · dbSNP, rs12913832

CD36 Can you taste fat? (CD36) Keener fat detection Mixed evidence

Whether your genes tune how well you detect fat as a taste on the tongue, separate from texture or smell. A common variant near the fat-sensing receptor gene shifts oral fat sensitivity a little; habit and overall diet dominate.

Your genotype: G/G (Taste & smell)
Most-associated reading: Keener fat detection

You carry two copies of the reference allele linked in some studies to keener oral fat detection.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: Association studies, Pepino et al. 2012, Journal of Lipid Research, CD36 and oral fat perception
Effect: The A allele has been linked in several studies to lower CD36 expression and reduced oral sensitivity to fat (a higher detection threshold), while the reference G allele tracks keener fat detection. Results vary across cohorts, so the direction is not universal.

CD36 is a receptor on taste cells that binds long-chain fatty acids; lower receptor levels are thought to raise the threshold at which fat is detected as a taste.

An inconsistent association across studies and populations. Whether you notice fat in food is mostly about texture, aroma and habit, not this single marker.

What this isn’t: Not a diagnosis and not a diet prescription; it describes a small difference in oral fat detection.

Pepino et al. 2012, J Lipid Res, CD36 and oral fat perception (PMID 22045638) · dbSNP, rs1761667

IRF4 Freckles & premature greying (IRF4) Steady pigment baseline Established biology · inferred call

One of the loudest single-SNP voices in cosmetic genetics: a variant linked to facial freckling, fair sun-sensitive skin, lighter childhood hair, and a tendency toward earlier hair greying. Mostly characterised in European-ancestry people, and still only one voice in a big choir.

Your genotype: C/C (Appearance & pigment)
Most-associated reading: Steady pigment baseline

Typical melanin production: on average fewer freckles, less sun-sensitivity, and later greying relative to T carriers.

How seriously to take this: the evidence

Strength: Established biology · inferred call
Source of the claim: GWAS Catalog (Han et al. 2008) + Praetorius et al. 2013 (Cell) enhancer mechanism: a rare case where one pigment SNP carries an outsized, mechanistically nailed-down effect
Effect: The T allele is linked to more facial freckling, fairer and more sun-sensitive skin, lighter (blonder) childhood hair, and a tendency toward earlier greying. Effect sizes are real but modest and overwhelmingly characterised in European-ancestry samples, so the read-out is most informative there. Think of it as one loud voice in a large choir, not a verdict.

rs12203592 sits in an IRF4 intron inside a melanocyte enhancer; the T allele weakens IRF4/TFAP2A-driven activation of tyrosinase (TYR), the rate-limiting melanin enzyme. Less TYR signalling means less melanin: hence lighter pigment, freckling, and (because the same machinery maintains hair-follicle melanocytes) earlier loss of hair colour.

Pigmentation and greying are highly polygenic; this one SNP explains only a slice of the variance and its allele frequencies and effects are calibrated to European-ancestry populations.

What this isn’t: Not a disease marker and not a deterministic predictor: a probabilistic, cosmetic-trait nudge.

dbSNP: rs12203592 · Praetorius et al. 2013, Cell: IRF4 enhancer regulates pigmentation via TYR

TENM2 Rage at chewing sounds: misophonia (TENM2) Reference / ancestral pair Single study

The marker behind 23andMe's famous 'filled with rage by the sound of someone chewing' study: the genetics of misophonia. About 1 in 5 surveyed people reported that reaction, and this spot was the standout hit. A fun 'is it just me?' curiosity, not a diagnosis.

Your genotype: G/G (Senses & quirks)
Most-associated reading: Reference / ancestral pair

Both copies are the ancestral G allele: the baseline genotype against which the association is measured.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: One very large 23andMe self-report GWAS (Front. Neurosci. 2022; ~80k+ European-ancestry participants): genome-wide significant, but a single consumer cohort, self-reported, intronic
Effect: This variant sits near TENM2, the gene 23andMe flagged in its 'rage at the sound of chewing' study. About 1 in 5 surveyed customers reported that reaction, and this marker came up as the standout hit. It's a fun curiosity, not a clinical result, and almost entirely European-ancestry data.

TENM2 (teneurin-2) is a cell-adhesion protein highly active in neurons during brain development and wiring. The hypothesis is that variation here subtly tunes circuits handling sound and emotion, possibly heightening reactions to repetitive noises, but the variant is intronic and its functional effect is unproven.

This rests on a single self-reported GWAS of one symptom, not a clinical misophonia diagnosis, and almost entirely European-ancestry data. Association is not causation, and the intronic variant's biology is unknown.

What this isn’t: Not a misophonia test or diagnosis: a statistical nudge tied to one self-reported sound-rage question.

dbSNP: rs2937573 · 23andMe misophonia GWAS (Front. Neurosci. 2022)

6p24 Motion sickness (carsick / seasick tendency) Typical Replicated · small effect

Whether your genes tilt you toward feeling carsick, seasick or queasy reading in a moving vehicle. One of many common variants nudges the odds; motion sickness is highly polygenic and very situational.

Your genotype: C/C (Quirks & reflexes)
Most-associated reading: Typical

You don't carry the motion-sickness-associated G allele at this marker. You can still get carsick: most of the trait is other genes and the situation.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS (NHGRI-EBI GWAS Catalog): Hromatka et al. 2015, 23andMe research cohort (PMID 25628336)
Effect: The G allele was associated with modestly higher odds of motion sickness in a very large self-reported study. It is one of many small-effect markers: each one, including this, explains only a sliver of why some people get carsick and others don't.

Motion sickness is thought to arise from conflicting signals between the inner ear and the eyes; the associated markers point loosely toward inner-ear development and neurological processing, with no single clear mechanism.

A modest, real association from a large GWAS, but motion sickness is highly polygenic and dominated by the situation: the boat, the back seat, the book. This SNP barely moves the needle for any one person.

What this isn’t: Not a diagnosis and not a prediction that you will (or won't) be sick on the next ferry.

NHGRI-EBI GWAS Catalog: rs2153535 (motion sickness) · Hromatka et al. 2015, Human Molecular Genetics: GWAS of motion sickness (PMID 25628336) · dbSNP: rs2153535

ZEB2 Sun sneeze: the ACHOO reflex (near ZEB2) More likely to sun-sneeze Replicated · small effect

Whether your genes tilt you toward sneezing when you step into bright light, sometimes called the photic sneeze reflex or ACHOO. A common variant near a neural-development gene nudges the odds; the reflex is harmless and situational.

Your genotype: C/C (Quirks & reflexes)
Most-associated reading: More likely to sun-sneeze

You carry two copies of the reference allele linked to higher odds of the photic sneeze reflex. Many C/C people never notice it.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS (23andMe research cohort), Eriksson et al. 2010, PLoS Genetics; replicated in a Chinese cohort, Wang et al. 2019
Effect: The reference C allele was associated with higher odds of the photic sneeze reflex. The effect is modest and the reflex is a curiosity.

The variant lies in an intergenic region of 2q22 near ZEB2, a gene involved in neural-crest and cranial-nerve development; the precise mechanism for light-triggered sneezing is not settled.

A modest, replicated association, but light-triggered sneezing is influenced by many factors and the variant only nudges the odds.

What this isn’t: Not a diagnosis and not a medical condition; the photic sneeze reflex is a harmless quirk.

Eriksson et al. 2010, PLoS Genetics, web-based GWAS of common traits (PMID 20585627) · dbSNP, rs10427255

MC1R Red hair & freckling (MC1R R151C) No R151C red-hair allele Established biology · inferred call

One of the famous 'ginger' switches in MC1R, the master dial for red hair, pale skin and freckles. One of the strongest single-SNP cosmetic effects in the genome, but the very same variant also means more sun-sensitivity, so it carries a real health note, not just a fun fact.

Your genotype: C/C (Appearance & pigment)
Most-associated reading: No R151C red-hair allele

You don't carry this particular loss-of-function variant: if you have red hair or freckles, other MC1R alleles or genes are responsible.

How seriously to take this: the evidence

Strength: Established biology · inferred call
Source of the claim: Large GWAS + decades of MC1R pigmentation genetics and functional receptor studies: R151C is one of the classic, heavily replicated red-hair 'R' alleles (red-hair OR ~12)
Effect: Carrying two loss-of-function copies strongly tilts toward red or strawberry-blond hair, fair freckly skin, and a tendency to burn rather than tan; one copy often shows up as freckles, lighter colouring, or red highlights in beard/body hair. It is one of the strongest single-SNP cosmetic effects in the genome, though other MC1R variants and genes also vote (it acts roughly recessively for red hair).

MC1R is a receptor on melanocytes that, when activated, switches pigment production toward dark brown/black eumelanin. The R151C change cripples receptor signalling, so cells default to making reddish-yellow pheomelanin instead: the pigment behind red hair and freckles. Less eumelanin also means less natural UV shielding in the skin.

Health note: the same loss-of-function alleles that produce red hair and fair skin also carry meaningfully higher sun-sensitivity and elevated melanoma (and other skin-cancer) risk, even in carriers who don't look obviously red-haired. This is a real reason that sun protection matters more, not just a cosmetic curio.

What this isn’t: Not a complete red-hair test and not a melanoma diagnosis: one major variant among several MC1R alleles, and hair, skin tone and cancer risk each depend on more than this site.

ClinVar/dbSNP: rs1805007 (MC1R R151C) · dbSNP: rs1805007

TRPV1 Chili-heat sensitivity (TRPV1) Reference receptor form Mixed evidence

A variant in the actual protein that fires when capsaicin (the 'heat' in chili) hits your tongue. A fun candidate for 'why is everyone at the table sweating but me?', though the genetic effect is small and the studies disagree.

Your genotype: T/T (Taste & smell)
Most-associated reading: Reference receptor form

Both copies encode the common Ile585 channel: the baseline, most-common version of the capsaicin receptor.

How seriously to take this: the evidence

Strength: Mixed evidence
Source of the claim: Small candidate-gene/functional studies on capsaicin sensitivity (not a large GWAS): direction inconsistent across studies
Effect: TRPV1 is literally the protein that fires when capsaicin hits your tongue, so it's a fun candidate for chili tolerance. Some studies suggest the 585Val (C) form is associated with slightly different sensitivity to capsaicin and warmth, but studies disagree on which allele raises or lowers sensitivity. Treat any personal read as a curiosity, not a verdict on your hot-sauce tolerance.

TRPV1 is a heat- and capsaicin-gated ion channel on sensory neurons; activating it produces the burning sensation. The Ile585Val substitution sits in the channel protein and may subtly tweak how readily it opens, plausibly nudging perceived heat intensity.

Studies disagree on which allele raises or lowers sensitivity, and effects are small versus huge non-genetic factors (habituation, diet, the specific chili). Don't over-read your genotype.

What this isn’t: Not a measure of how much you 'like' spicy food or your overall pain tolerance: only one input into capsaicin perception.

dbSNP: rs8065080 · Ensembl: rs8065080 (TRPV1 Ile585Val)

TAS1R3 How sweet is sweet? Sucrose sensitivity (TAS1R3) Lower sweet sensitivity Single study

Whether your genes make table sugar taste more or less intense to you. A variant in the promoter of the sweet-taste receptor gene tunes how sensitive your tongue is to sucrose. This is about perceived intensity, not how much you like sweets.

Your genotype: T/T (Taste & smell)
Most-associated reading: Lower sweet sensitivity

You carry two copies of the reference allele linked to lower sucrose sensitivity; sugar may register a touch less intensely.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: Genetic and functional study, Fushan et al. 2009, Current Biology, a TAS1R3 promoter variant and sucrose sensitivity
Effect: The C allele tracks higher promoter activity and greater sensitivity to sucrose; the reference T allele tracks lower activity and reduced sweet sensitivity. The site was reported to explain roughly a sixth of the population variability in sucrose perception.

TAS1R3 is part of the sweet-taste receptor; the variant sits in the gene's promoter and changes how much receptor is made, tuning the strength of the sweet signal.

A notable single-cohort signal, but how sweet a food seems also depends on temperature, the other sweet-receptor subunit and what you are used to. Sensitivity is not the same as preference.

What this isn’t: Not a diagnosis and not a measure of how much you crave sugar; it describes perceived intensity.

Fushan et al. 2009, Current Biology, TAS1R3 and sucrose sensitivity (PMID 19559618) · dbSNP, rs35744813

FGF21 Sweet tooth (FGF21 'sugar hormone') Leans toward sweets Replicated · small effect

Whether your genes nudge you toward a sweet tooth. FGF21 is a liver hormone that helps regulate sugar intake; a common variant near it shifts the odds a little, but habit, culture and appetite dominate.

Your genotype: A/A (Taste & appetite)
Most-associated reading: Leans toward sweets

You carry the A allele linked to a slightly higher relative sugar intake. Plenty of A/A people have no special sweet tooth at all.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS (NHGRI-EBI GWAS Catalog): FGF21 macronutrient / sweet-food-liking studies (Søberg et al. 2017 and later relative-sugar-intake GWAS)
Effect: The A allele was associated with a slightly higher relative sugar intake, and the G allele with slightly lower liking of sweet foods. The per-allele effect is tiny: a faint nudge on a behaviour that is overwhelmingly about habit, availability and appetite.

FGF21 is a hormone released by the liver that acts on the brain to help regulate sugar and macronutrient preference; common variation near the gene appears to fine-tune that signal.

A small, real, but easily-overwhelmed effect. Your sweet tooth is mostly your kitchen and your habits, not this one SNP.

What this isn’t: Not a diagnosis, not a diet prescription, and not a verdict on your willpower or your weight.

NHGRI-EBI GWAS Catalog: rs838133 · dbSNP: rs838133

SLC45A2 Tan vs burn: skin pigment (SLC45A2) Two darker copies: reliable tan Established biology · inferred call

A heavyweight 'tan vs burn' switch and one of the most strongly selected pigment genes in the genome. The lighter allele is near-universal in Europeans and pushes toward fair skin that goes pink rather than golden; the darker allele tans more reliably. A real sun-sensitivity note, not just a cosmetic one.

Your genotype: C/C (Appearance & pigment)
Most-associated reading: Two darker copies: reliable tan

374Leu/Leu: most melanin, best tanning and baseline UV defence. Rare in European-ancestry samples.

How seriously to take this: the evidence

Strength: Established biology · inferred call
Source of the claim: Classic pigmentation genetics: repeatedly replicated across European, East-Asian, South-Asian and South-American studies; among the strongest signals of positive selection in the human genome
Effect: The light allele (G / Phe374) is near-fixed in Europeans and pushes toward fairer skin, lighter hair and eyes, and a tendency to go pink rather than golden in the sun. Carrying the darker allele (C / Leu374) generally means more reliable tanning and more baseline UV protection. Effects are best characterised in European and admixed populations; magnitude varies with overall pigment background.

SLC45A2 sits in the melanosome membrane and helps regulate melanosomal pH; the right pH lets tyrosinase work and dark eumelanin accumulate. The 374Phe variant reduces effective pigment production, so melanocytes make less protective melanin: hence lighter colouring and a faster sunburn.

Sun-sensitivity-relevant, not just cosmetic: the light (G/Phe374) allele tracks higher sunburn susceptibility and appears in melanoma case-control work, while the darker allele is associated with protection. Genotype is no substitute for sunscreen, and this single SNP does not estimate personal cancer risk.

What this isn’t: Not a melanoma test or a clinical diagnosis: one well-studied dial among many that influence pigment and UV response.

dbSNP: rs16891982 · Evolution of skin-pigmentation variation in West Eurasia (PNAS)

CA6 Tongue taste-bud density: gustin (CA6) Higher papilla density (stronger-taster-leaning) Single study

Whether your genes nudge how many fungiform papillae (the little taste-bud-bearing bumps) you have on your tongue, which tracks loosely with being a stronger or weaker taster. A variant in the salivary gustin gene shifts the odds; it pairs with, but is separate from, the bitter-taste gene.

Your genotype: A/A (Taste & smell)
Most-associated reading: Higher papilla density (stronger-taster-leaning)

You carry two copies of the reference allele tracking the more functional gustin protein and higher fungiform papilla density.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: Functional and association studies, Melis et al. 2013, PLoS One, gustin (CA6) and fungiform papilla density
Effect: The reference A allele (Ser90) tracks the more functional protein, higher fungiform papilla density and a stronger-taster tendency; the G allele (Gly90) tracks fewer papillae and a weaker-taster tendency. The effect is modest and from a small number of cohorts.

CA6 (gustin) is a protein in saliva thought to support the growth and maintenance of fungiform papillae; the amino-acid change alters its activity, affecting papilla density and so taste-bud number.

A modest, single-group signal. Papilla counts vary for many reasons and the link to overall taste strength is loose; the bitter-taste receptor gene plays a larger role for bitterness itself.

What this isn’t: Not a diagnosis and not a verdict on whether you are a supertaster; it is one small input to taste-bud density.

Melis et al. 2013, PLoS One, gustin (CA6) and fungiform papillae · dbSNP, rs2274333

EDAR Hair thickness and shovel-shaped teeth (EDAR) Typical hair and tooth pattern Replicated · small effect

A single variant that arose in ancient East Asia and spread to Native American populations shifts several body traits at once: thicker, straighter hair fibres, scooped (shovel-shaped) front teeth, more sweat glands and subtle face shape. It is rare in European and African ancestry.

Your genotype: A/A (Appearance)
Most-associated reading: Typical hair and tooth pattern

You carry two copies of the reference allele, the common pattern in European and African ancestry; the EDAR trait cluster is not expected.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: Functional and association studies, Kimura et al. 2009, American Journal of Human Genetics; mouse-model work by Kamberov et al. 2013
Effect: The G allele (the derived 370A form) tracks thicker and straighter hair shafts, shovel-shaped incisors, more eccrine sweat glands and subtle changes in chin and ear shape. The reference A allele tracks the more typical European and African pattern. The G allele is at very high frequency in East Asian and Native American ancestry and near-absent elsewhere.

EDAR is a receptor that guides the development of hair follicles, teeth and sweat glands; the derived allele increases EDAR signalling, producing the linked set of traits.

A real, well-replicated set of effects, but each trait also depends on other genes, age and grooming. The associations are clearest in populations where the allele is common.

What this isn’t: Not a diagnosis and not an ancestry test, though the allele frequency varies strongly by ancestry.

Kimura et al. 2009, Am J Hum Genet, EDAR and shovel incisors (PMID 19804850) · dbSNP, rs3827760

TAS1R1 Umami (savory) taste sensitivity (TAS1R1) Baseline umami receptor Single study

Whether the savory 'fifth taste' of broth, parmesan, soy sauce and ripe tomatoes leaps out at you or barely registers. This TAS1R1 spot is one nudge in that dial: a fun hint, not a verdict on your palate.

Your genotype: G/G (Taste & smell)
Most-associated reading: Baseline umami receptor

Two ancestral Ala372 copies: the typical setup; nothing here points to heightened or dulled savoury sensitivity.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: Functional cell-based + small psychophysical taste-threshold studies (Shigemura 2009); later cohorts give mixed results: suggestive rather than established
Effect: The A (Thr372) version of the umami receptor has been linked in lab and small taste-test studies to a more sensitive umami receptor: picking up savoury flavours at lower concentrations. The effect is modest and one of many ingredients, so treat it as a fun hint, not a verdict. Replication has been inconsistent across populations.

TAS1R1 pairs with TAS1R3 to form the tongue's umami receptor, which detects glutamate (and is boosted by nucleotides like those in dried mushrooms and cured fish). The Ala372Thr swap sits in the receptor's large extracellular domain, and the Thr version appears to make the receptor respond at lower glutamate levels.

Umami perception is polygenic and strongly shaped by culture, diet and age, so a single SNP explains only a sliver. Replication has been inconsistent across populations.

What this isn’t: Not a measure of how much you like savoury food or your overall 'supertaster' status: only one small genetic input to umami sensitivity.

dbSNP: rs34160967 · Shigemura et al. 2009, PLOS ONE: individual differences in human umami taste

PAX3 Eyebrow convergence: the 'unibrow' nudge (PAX3) Brows likely to keep their distance Single study

A marker the big Latin-American facial-features GWAS tied to how close together your eyebrows grow: your odds of a faint (or frank) middle-of-the-forehead bridge. A gentle statistical nudge, not a verdict, and grooming always has the final say.

Your genotype: C/C (Face & features)
Most-associated reading: Brows likely to keep their distance

Typical separated-eyebrow pattern: the lowest monobrow tendency at this marker.

How seriously to take this: the evidence

Strength: Single study
Source of the claim: Adhikari et al. 2016 (Nat Commun): genome-wide significant at the PAX3 monobrow locus in ~6,000 admixed Latin Americans; biologically coherent (PAX3→Waardenburg synophrys), not broadly replicated across ancestries
Effect: This marker sits in DNA downstream of PAX3 that the GWAS tied to how close together your eyebrows grow. The A allele nudges toward greater eyebrow convergence. The effect is a gentle statistical nudge, not a verdict: plenty of people with the 'more-convergent' allele have perfectly tidy brows. Discovered in admixed Latin Americans, so the effect size in European/Finnish brows may differ.

PAX3 is a master regulator of neural-crest derivatives, including pigment cells and the patterning of facial/hair structures; rare coding PAX3 mutations cause Waardenburg syndrome, in which joined brows (synophrys) is common. This common variant likely tweaks PAX3 regulation subtly rather than breaking it, dialling brow-hair distribution up or down.

A regulatory/intergenic common variant, not the Waardenburg disease mutation: it carries no disease implication on its own, and the effect estimates come from one ancestry group.

What this isn’t: Not a diagnosis of any syndrome, and it does not predict hearing, eye colour or any health outcome.

Adhikari et al. 2016, Nat Commun: facial & scalp-hair GWAS in Latin Americans · dbSNP: rs2395845

OR5A1 Can you smell violets? Beta-ionone (OR5A1) Highly sensitive to violets Replicated · small effect

Whether your genes make you highly sensitive to beta-ionone, the floral, violet-like aroma used in perfumes and added to some foods and wines. A single variant in one smell receptor explains most of this near-on-or-off difference.

Your genotype: G/G (Taste & smell)
Most-associated reading: Highly sensitive to violets

You carry two copies of the reference allele linked to high sensitivity to beta-ionone; the floral, violet-like note tends to stand out to you.

How seriously to take this: the evidence

Strength: Replicated · small effect
Source of the claim: GWAS and functional study, Jaeger et al. 2013, Current Biology, a Mendelian olfactory-sensitivity trait
Effect: The reference G allele tracks high sensitivity: carriers of one or two G alleles detect beta-ionone at far lower concentrations than A/A individuals, and tend to describe it as fragrant, floral and violet-like. The A allele (Asn183) tracks low sensitivity. This single site explains most of the variation.

OR5A1 is an odorant receptor; the amino-acid change at position 183 alters how strongly the receptor responds to beta-ionone, behaving almost like a single-gene on-or-off switch.

An unusually strong single-gene effect for a smell trait, but how you describe an aroma also depends on context, concentration and experience.

What this isn’t: Not a diagnosis and not a general verdict on your sense of smell; it is specific to one floral compound.

Jaeger et al. 2013, Current Biology, Mendelian olfactory sensitivity (PMID 23910657) · dbSNP, rs6591536

Ancestry

Your deep maternal (mitochondrial) and paternal (Y-chromosome) lines as haplogroups, restated from the published PhyloTree (mtDNA) and ISOGG (Y-DNA) trees. A haplogroup traces one single line, a single thread out of the thousands of ancestors who make you. It is not your ethnicity, your nationality, or a "percent ancestry" figure.

Maternal line · mtDNA Maternal line · mtDNA

No mitochondrial (mtDNA) variants were found in your file, so we can't place your maternal line. A standard variant file can't tell an all-reference mitochondrion apart from one that wasn't sequenced, so treat this as a gap, not a result.

Paternal line · Y-DNA Paternal line · Y-DNA

No Y-chromosome haplogroup markers were found in your file, so we can't place your paternal line. This is expected if you are biologically female (there is no Y chromosome to read), if your file didn't cover the Y, or if your paternal line matches the reference at the sites we read (most often the Western-European R1b line). A variant file can't tell these apart, so treat this as a gap rather than a result.

What this module does not do (3)

Named on purpose: the gaps are the trust signal. A haplogroup is one line, not a whole family tree.

Admixture / “percent ancestry” estimates: these need reference panels and carry the same ancestry-bias and framing problems as polygenic scores, so they are deliberately deferred rather than faked from a single-line haplogroup.
Finer subclade resolution within these broad clades (for example mtDNA L2a within L2 or U5 within U, or Y subclades such as E-M2 or O-M122 detail), a planned expansion as the trees we report against grow.
Maternal haplogroup B, whose defining signature is a short (9-base) deletion that our single-letter-variant analysis can't yet read, a planned addition alongside that capability.

Sources & versions

Every finding is restated from these pinned, openly-licensed sources.

ACMG SFv3.3
ClinVarunpinned
Ensembl VEPunpinned
gnomADunpinned
CPIC2026-06 snapshot
GWAS Catalog2026-06 snapshot
PhyloTree (mtDNA)Build 17
PGS Catalog2026-06 snapshot

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