Distribution of Genetic Polymorphisms in Drug Metabolizing Gene Cytochrome P450 (CYP2C8*3 and CYP2C9*2) in a North Indian Type 2 Diabetes Population

Background and objective(s): Diabetes is growing as an epidemic, with around 250 million diabetics estimated globally and which is expected to rise up to 380 million in the next 15 years. Differences in the efficacy and toxicity of various antidiabetic drugs have been linked to polymorphisms in various drug metabolizing enzymes. In this study we have investigated the frequency of occurrence of two single nucleotide polymorphisms in the CYP gene (CYP2C8*3 and CYP2C9*2) in type 2 diabetes mellitus (T2DM) patients from North India. Methods: This study included 360 T2DM patients from North India. Real-time polymerase chain reaction was carried out for the evaluation of specific CYP450 gene polymorphisms via the specific TaqMan® SNP genotyping assays (Applied Biosystems Inc.) for detection of CYP2C8*3 (rs10509681) and CYP2C9*2 (rs1799853) polymorphisms in the CYP450 gene. Results: For the CYP2C8*3 polymorphism, the genotype frequencies detected were 0%, 92.78% and 7.22% for CC, TT and CT genotypes while the frequency of the C allele was 3.61% and that of the T allele was 96.39%. For the CYP2C9*2 (rs1799853) polymorphism, the frequencies were 3.1%, 12.5% and 84.44% for CC, AA and CA genotypes. The frequency of occurrence of A and C alleles were 54.72% and 45.28% respectively. Conclusions: Frequency of occurrence of the T and A alleles of CYP2C8*3 (rs10509681) and CYP2C9*2 (rs1799853) polymorphisms was higher in T2DM patients from North India.