Association of SLC30A8, CDKAL1, TCF7L2 and HHEX Gene Polymorphisms with Type 2 Diabetes in the Population of North East India

Abstract

India currently has the second largest number of individuals suffering from diabetes across the world. Hence, it is pertinent to explore the genetic variations in Indian populations to comprehend the extent of genetic heterogeneity. We studied the association of gene variations of four candidate genes [SLC30A8 (rs11558471), CDKAL1 (rs94655871), TCF7L2 (rs12255372) and HHEX (rs1111875)] with Type 2 Diabetes (T2D) in the North East Indian population on whom there is very little data available. DNA was extracted from 155 diabetic patients and 100 non-diabetic controls. Genotyping was performed by Polymerase chain reaction-Restriction fragment length polymorphism (PCR-RFLP). Logistic regression analysis was performed to detect the association between genetic variants and type 2 diabetes. The CT genotype of rs9465871 (CDKAL1 gene) showed significant protection against diabetes [OR = 0.39 (0.17–0.91), p = 0.029] as compared to the CC genotype even after adjusting for age, sex and BMI. When analysed under a recessive model, the GG genotype of rs1111875 (HHEX gene) also showed significant protection against diabetes [OR = 0.38 (0.18–0.82), p = 0.014] as compared to the AA+AG genotypes. Both these findings did not remain significant after Bonferroni threshold of p = 0.0041 was applied. There is considerable variation in the pattern of association of these genes with T2D amongst the North East Indian population, when compared to the other ethnically and geographically diverse Indian populations.