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CYP2C9*3
Introduction
Cytochrome P450 2C9 (CYP2C9), a member of the CYP2C enzyme subfamily, ranks amongst the most
important drug metabolizing enzymes in humans.
Human CYP2C9 has been shown to exhibit genetic polymorphism. In addition to the wild-type protein CYP2C9*1, at least 32 single nucleotide polymorphisms (SNPs) have been reported within the coding region of the CYP2C9 gene producing the variant allozymes. CYP2C9*3 is one of them. CYP2C9*3 reflects an Ile359-Leu (I359L) change in the amino acid sequence, and have reduced catalytic activity compared with the wild type (CYP2C9*1).
Allele frequencies(%) of CYP2C9 polymorphism
| African-American | Black-African | Pygmy | Asian | Caucasian | |
|---|---|---|---|---|---|
| CYP2C9*3 | 2.0 | 0-2.3 | 0 | 1.1-3.6 | 3.3-16.2 |