From SNPedia
| ? | (A;A) (A;G) (G;G) | 28 |
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is a SNP in the
CYP2C19 gene, potentially encoding the CYP2C19*4 variant. This variant has been linked to poor metabolism of compounds like mephenytoin. It is also known as M1V or Met1Val.[
PMID 9435198]
The risk allele is rs28399504(G).
As a nonfunctioning CYP2C19, this variant would be expected to be a poor metabolizer of several commonly prescribed drugs, including anti-ulcer drugs like omeprazole (trade names Losec and Prilosec), esomeprazole (trade name Nexium), and lansoprazole (Prevacid).
According to a 23andMe discussion This is one of the SNPs which were re-analyzed April 2009. Customers with older data may wish to redownload. SNPs effected rs4420638, rs34276300, rs3091244, rs34601266, rs2033003, rs7900194, rs9332239, rs28371685, rs1229984, and rs28399504.
| PharmGKB | PA162363762 |
| Name | CYP2C19*4, CYP2C19:A1G |
| Annotation | Subjects who had previously experienced myocardial infarction and were receiving clopidogrel were almost twice as likely to experience a subsequent cardiovascular event if they carried any two CYP2C19 loss-of-function alleles (CYP2C19*2, CYP2C19*3, CYP2C19*4 or CYP2C19*5) relative to those with none. Patients from this study who underwent percutaneous coronary intervention and carried two CYP2C19 loss-of-function alleles had a 3.58 times greater risk of cardiovascular events as those with none. These results suggest that treatment with clopidogrel is less effective in individuals who are homozygous for CYP2C19 loss-of-function alleles than in those who do not carry CYP2C19 loss-of-function alleles. |
| Gene | CYP2C19 |
| Featue | Exon |
| Evidence | PubMed ID:19106083 |
| Drugs | clopidogrel |
| Diseases | Cardiovascular Diseases, Death, Myocardial Infarction, Stroke |
| Curation Level | Curated |
| PharmGKB | PA162316733 |
| Name | CYP2C19*4, 1A>G, 99C>T, 80161A>G |
| Annotation | This allele was examined in a European Caucasian population which had been phenotyped for mephenytoin metabolism. Based on the genotyping results the authors conclude that the defective nature of the CYP2C19*4 allele is shown by the fact that two Caucasian poor metabolizers were heterozygous for CYP2C19*2/CYP2C19*4. In vitro experiments showed no expression of CYP2C19*4 cDNA. The study calculated that the frequency of the CYP2C19*4 allele in Caucasians was 0.6%. |
| Gene | CYP2C19 |
| Featue | Exon |
| Evidence | PubMed ID:9435198 |
| Drugs | mephenytoin |
| Diseases | |
| Curation Level | Curated |
[PMID 21247447] CYP2C19 and ABCB1 gene polymorphisms are differently distributed according to ethnicity in the Brazilian general population
