Frequencies of VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 genetic variants in the Northern Indian population.

Dose requirements for oral anticoagulants in thromboembolic events are influenced by polymorphisms in VKORC1 and CYP2C9 genes. The Indian population comprises multiple ethnic groups but no data is available on allele frequencies of these genes for North Indians. The present study aimed at establishing the allele and genotype frequencies of VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 alleles in the North Indian population. One hundred and two healthy subjects from the Northern Indian region were genotyped for VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 by polymerase chain reaction and restriction fragment length polymorphism. Allele frequencies were compared with that of the HapMap populations. The allele frequencies for VKORC1 -1639 A, CYP2C9*2 and CYP2C9*3 were found to be 14.22%, 4.90% and 3.92% respectively. This report also describes the inter-ethnic differences in the Northern Indian frequencies of VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 alleles with that of other populations and HapMap project data. VKORC1 -1639 G>A allele is present at moderately high frequency in the Northern Indian population. The frequencies of CYP2C9*2 and CYP2C9*3 alleles are also found to be different from other populations.