Transcription factor 7-like 2 gene, rs12255372 (G/T) variant and susceptibility to type 2 diabetes mellitus in North Indians

Background: Genetic polymorphisms of the Transcription Factor 7-Like 2 (TCF7L2) gene have been shown to be strongly associated with susceptibility to type 2 diabetes mellitus (T2DM) and its related complications across several ethnicities. Objectives: The aim of the present study was to investigate the association of rs12255372 (G/T) polymorphism in TCF7L2 gene with the risk of T2DM in the Indian population. Methods: We included a total of 712 human subjects (327 T2DM subjects and 385 healthy controls) for various anthropometric, biochemical and genetic parameters. Genotyping of TCF7L2 gene was carried out using the PCR-RFLP method. Results: Significantly higher values of body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), and body fat (%) were observed in T2DM subjects than controls (p <= .001). Dyslipidemia represented by higher levels of triglycerides and reduced values of high-density lipoprotein (HDL) was more predominant in T2DM subjects compared to healthy controls. Both microvascular and macrovascular complications were predominant in T2DM patients than controls. The risk genotype (TT) frequency of TCF7L2 gene was significantly higher in T2DM subjects compared to controls (19.4% vs. 9.8%). The "T" allele was more predominant in T2DM subjects than healthy controls. Logistic regression analysis of the data indicates that the TT genotype of TCF7L2 gene is associated with appox. 2-fold increased risk of developing T2DM (OR = 1.91 95% CI (1.16-3.16); p = .014). Interestingly, no significant association among the genotypic distribution of metabolic traits in T2DM and healthy subjects. Conclusion: The present study established a significant association of TCF7L2 gene (rs12255372 (G/T) polymorphism) with a higher risk of T2DM in the North Indian population.