Polymorphisms at CYP and GST gene loci: prevalence in the Indian population

Abstract

Objective: The aim of the present study was to investigate the distribution of the CYP1A1∗ 3 and CYP2D6∗ 4 alleles, the null genotype at the GSTM1 and GSTT1 gene loci, the GSTM1 C₅₃₄-G₅₃₄ polymorphism and the GSTM3 intron-6 polymorphism in the Indian population. Methods: DNA extracted from the blood samples of 883 individuals was subjected to polymerase chain reaction (PCR) followed by restriction digestion, wherever required. Results: The CYP1A1∗3/∗3 and CYP2D6∗4/∗4 genotypes were present in 1.6% of the Indian population. The frequencies of the GSTM1 A/A, A/B, B/B and 0/0 genotypes were 30.2%, 6.6%, 36.5% and 26.6%, respectively, while the GSTM3B/B and GSTT1 null genotypes were present in 1.2% and 13.0% of the population, respectively. Conclusion: A comparison of these findings with data in other ethnic groups points to the distinctive nature of the Indian population with respect to polymorphisms at the GST and CYP gene loci.