ABCG2: the second transporter in the rosuvastatin story
ABCG2 is a small page for a narrow question: it changes how much rosuvastatin ends up in your blood. That is the whole of its guideline scope, and pretending otherwise would be padding.
Also known as: BCRP, breast cancer resistance protein, ATP binding cassette subfamily G member 2.
What ABCG2 does
ABCG2 makes a pump, usually called BCRP, that sits in cell membranes in the gut and the liver and pushes certain drugs back out. For rosuvastatin the practical effect is on absorption and clearance: a weaker pump means more of the drug gets in and less of it leaves, so the same tablet produces higher blood levels. The gene has a second life outside pharmacology as a determinant of uric acid handling, which is why you may see it mentioned in the context of gout, but that is not what CPIC grades it for and not what Aimosti reports here.
The transporter function groups
The grading is short because the evidence is. CPIC recognises normal function, decreased function and poor function for ABCG2, driven mainly by one common variant, rs2231142, also written Q141K. One copy gives decreased function, two give poor function. There is no metabolizer scale here, because ABCG2 is a pump rather than an enzyme.
Medications where it matters
rosuvastatin (Crestor)
Rosuvastatin is the only drug in CPIC's ABCG2 guidance, and the recommendation is written for the pair of transporters rather than for this gene alone. The rows below assume a typical SLCO1B1 result. If your SLCO1B1 result is not typical, the two have to be read together, which is what the report does and what a prescriber would want to see.
| If your result is | Published CPIC guidance |
|---|---|
| Decreased Function | Per CPIC (A): "Prescribe desired starting dose and adjust doses of rosuvastatin based on disease-specific and specific population guidelines." |
| Normal Function | Per CPIC (A): "Prescribe desired starting dose and adjust doses of rosuvastatin based on disease-specific and specific population guidelines." |
| Poor Function | Per CPIC (A): "Prescribe ≤20mg as a starting dose and adjust doses of rosuvastatin based on disease-specific and specific population guidelines. If dose >20mg needed for desired efficacy, consider an alternative statin or combination therapy (i.e., rosuvastatin plus non-statin guideline directed medical therapy) (PMID: 30423391)." |
Is this in your raw DNA file?
ABCG2 is not part of the standard chip or variant-file report. It belongs to the Deep Read panel, which runs from aligned reads in a BAM or CRAM file. That is a deliberate limit rather than an oversight: the CPIC guidance for ABCG2 is only meaningful next to a SLCO1B1 result, and the pairing is what the Deep Read panel is for. Where the reads do not resolve the genotype, the answer is reported as unresolved rather than assumed to be reference.
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.
Common questions
Is ABCG2 in my 23andMe or AncestryDNA raw data?
The main variant sits at a position some consumer chips carry, but Aimosti does not report ABCG2 from a chip file. It is a Deep Read gene, read from aligned reads, because its guidance only makes sense paired with SLCO1B1.
I have seen ABCG2 linked to gout. Is that in the report?
No. The uric-acid association is real and well studied, but it is not pharmacogenomic guidance and CPIC does not grade the gene for it. This page and the Deep Read panel stay inside what CPIC publishes, which for ABCG2 means rosuvastatin.
Why is there only one drug here when the statin guideline covers seven?
Because ABCG2 only carries weight for rosuvastatin. The other six statins in the same CPIC guideline are graded on SLCO1B1, sometimes with CYP2C9, and they appear on those pages instead.