Cha adult arab
Whereas the CYP2C9*2 and *3 alleles affect coumarin pharmacokinetics, the VKORC1 –1639GA polymorphism affects the pharmacodynamic response to coumarins .
It has been reported that polymorphisms in the CYP2C9 and VKORC1 genes together account for 35%–50% of the variability in COAs dose requirements for initiation and maintenance .
A total of 131 healthy adult subjects from the Al-Ahsa region of Saudi Arabia were genotyped for the CYP2C9Pharmacogenomics is the first step towards personalized medicine and is a promising field of investigation that may explain some of the interindividual variations in responses to various classes of drugs [1, 2].
Among other factors, interindividual COAs dose variability is significantly influenced by variations in the genes encoding two enzymes: cytochrome P450 2C9 (CYP2C9), the enzyme that metabolizes COAs, and vitamin K epoxide reductase (VKORC1), the pharmacologic target of these drugs .
Polymorphisms in the CYP2C9 gene seriously affect the enzymatic activity of the encoded CYP2C9 protein.
Based on phenotype, populations can be divided into extensive (EM), intermediate (IM), and poor metabolizers (PM), and more than 35 different allelic variants have been identified in the CYP2C9 gene .
Among these alleles, the CYP2C9*2 (rs1799853) and *3 (rs1057910) variants, which reduce CYP2C9 enzymatic activity, allow for the prediction of more than 85% of PMs .