Background In recent years, it is found that the polymorphisms of genes which are involved in the pharmacokinetic and pharmacodynamic pathways play important roles in the clinical anticoagulation treatment with warfarin. The aim of the study was to investigate the impact of the genetic polymorphism of r-glutamic acid carboxylase (gamma-glutamyl carboxylase gene, GGCX) on the response of warfarin initial anticoagulant therapy. Methods Seven hundred and ninety-eight Chinese Han patients who received valve replacement surgery and orally taken warfarin in long term for anticoagulant therapy in Guangdong General Hospital from 2000 to 2008 were enrolled in the study, a polymorphic SNPs point (rs699664) of GGCX was selected, and SnaPshot was adopted to perform single nucleotide polymorphism (SNP) test, and by grouping according to genotype, GGCX average daily dose of warfarin, time for PT-INR to reach the target value and differences in the incidence of excessive coagulation between different genotypes were compared respectively. Hardy-Weinberg genetic equilibrium test was applied for population representative test. Results Within the 20 days of warfarin initial therapy, male average daily dose of warfarin (2.92 ± 1.18 mg/d) was apparently higher than that of female (2.64 ± 0.98 mg/d), while there were no significant differences in the average time required for PT-INR to reach the target value ( > 1.8) and the excessive coagulation ratio at the initial therapy stage between male and female. And there were no significant differences in the average daily dose of warfarin, time to reach the target value and excessive coagulation ratio among different GGCX genotypes. Conclusions GGCX genovariation had no significant impact on the warfarin daily dose within the 20-day initial therapy of Chinese Han Population, and for the conventional dosage program, the risk of bleeding in the GGCX mutation individuals did not increase obviously at the initial administration period.
