Influence of CYP2C9 and VKORC1 Polymorphisms on Individual Warfarin Dose after Cardiac Valve Replacement

Objective To investigate characteristics of polymorphism distribution of cytochrome P450 2C9( CYP2C9) and vitamin K epoxide reductase complex 1( VKORC1) genotypes and the influence on Warfarin dose in Han population of Hubei Province. Methods A total of 108 patients of Han Nationality taking Warfarin in Hubei Province from March to August of 2012 were chosen as Warfarin group,and 85 healthy volunteers at the same period were chosen as control group. Genotypes of CYP2C9 and VKORC1 were detected with polymerase chain reaction-restriction fragment length polymorphism( PCR-RFLP) technique in the two groups,and stable Warfarin doses of different genotypes were also compared. Results There were no significant differences in distributions of genotype frequency and allele frequency( P 0. 05). In Warfarin group,stable Warfarin dose of patients with CYP2C9* 1 /* 3 type was significantly smaller than that of patients with CYP2C9* 1 / * 1,and stable Warfarin dose of patients with VKORC1 AA type were significantly smaller than that of patients with VKORC1 GA type( P 0. 05,P 0. 01). More than fifty variant sites were found in addition to the 3 detected polymorphic sites. Conclusion There are polymorphisms of CYP2C9 and VKORC1 in Han population of Hubei Province,and there are significant differences in stable Warfarin dosage in patients with different genotypes,but relevant Warfarin variant sites need to be further studied.