rs4244285 CYP2C19
CYP2C19*2 homozygous poor metabolizer. Clopidogrel may be ineffective; consider alternative antiplatelet.
What is rs4244285?
rs4244285 is a single-nucleotide polymorphism (SNP) in the CYP2C19 gene (Cytochrome P450 2C19). Each person carries two copies, one from each parent, so a result is reported as a pair of letters such as AA. The table below describes what studies associate with each genotype; the association is statistical, across populations, and is not a diagnosis.
What does each rs4244285 genotype mean?
| Genotype | Association | What the evidence says | Confidence |
|---|---|---|---|
| AA | reduced | CYP2C19*2 homozygous poor metabolizer. Clopidogrel may be ineffective; consider alternative antiplatelet. | 93% |
| GA / AG | reduced | CYP2C19*2 intermediate metabolizer. Reduced clopidogrel activation. | 90% |
| GG | typical | Normal CYP2C19 function. Standard clopidogrel response. | 92% |
How common is the A allele of rs4244285?
Minor-allele frequency by population (gnomAD / 1000 Genomes):
| European | 15.0% |
|---|---|
| East Asian | 30.0% |
| African | 15.0% |
| South Asian | 35.0% |
| Admixed American | 12.0% |
| Global | 21.0% |
Which drugs have annotations for rs4244285?
PharmGKB clinical annotations (level 1A is the strongest evidence, 4 the weakest):
| Drug | Annotation type | Evidence level |
|---|---|---|
| prasugrel | Efficacy, Toxicity, Metabolism/PK, Dosage, Other | 3 |
| venlafaxine | Efficacy, Toxicity, Metabolism/PK, Dosage, Other | 3 |
Is rs4244285 on 23andMe and AncestryDNA chips?
Yes — it is genotyped directly on 23andMe V3, 23andMe V4, 23andMe V5, AncestryDNA V1, AncestryDNA V2. Orviva reads it from a raw-data export without imputation.
Sources
Upload your 23andMe, AncestryDNA or WeGene raw file → · Ask G2: “What is my genotype at rs4244285 and what does it mean for me?”
Genetic associations describe risk across populations, not a diagnosis for any one person. Most variants shift risk modestly and act alongside lifestyle, environment and other genes. Consumer DNA chips do not read every position and can be wrong at any single one. For general education only; talk to a clinician or genetic counsellor before acting on anything here, and never change a prescribed medicine without your prescriber.