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rs12248560 CYP2C19

CYP2C19*17 homozygous ultra-rapid metabolizer. Increased clopidogrel activation; may increase bleeding risk.

Curated · human-reviewed Drug response · Risk / effect allele: T · dbSNP

What is rs12248560?

rs12248560 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 TT. The table below describes what studies associate with each genotype; the association is statistical, across populations, and is not a diagnosis.

What does each rs12248560 genotype mean?

GenotypeAssociationWhat the evidence saysConfidence
TTincreasedCYP2C19*17 homozygous ultra-rapid metabolizer. Increased clopidogrel activation; may increase bleeding risk.85%
CT / TCincreasedCYP2C19*17 carrier. Rapid metabolizer; enhanced drug activation.82%
CCtypicalNormal CYP2C19 metabolizer status.85%

How common is the T allele of rs12248560?

Minor-allele frequency by population (gnomAD / 1000 Genomes):

European21.0%
East Asian1.0%
African18.0%
South Asian15.0%
Admixed American15.0%
Global14.0%

Which drugs have annotations for rs12248560?

PharmGKB clinical annotations (level 1A is the strongest evidence, 4 the weakest):

DrugAnnotation typeEvidence level
mephenytoinDosage, Toxicity, Efficacy, Metabolism/PK3
cyclophosphamideDosage, Toxicity, Efficacy, Metabolism/PK3
doxorubicinDosage, Toxicity3

Is rs12248560 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

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.