Association of the TCF7L2 rs12255372 (G/T) variant with type 2 diabetes mellitus in an Iranian population

Faranak Mahmoudi Alami,Hamidreza Bazrafshan,Nader Mansour Samaei,Alijan Tabarraei,Mohammad Amin Tabatabaiefar,Ayyoob Khosravi,Mehran Ahmadi

doi:10.1590/s1415-47572012005000029

Abstract

In various populations worldwide, common variants of the TCF7L2 (Transcription factor 7-like 2) gene are associated with the risk of type 2 diabetes mellitus (T2DM). The aim was to investigate the association between rs12255372 (G/T) polymorphism in the TCF7L2 gene and T2DM in an Iranian population. 236 unrelated patients with T2DM, and 255 normoglycemic controls without diabetes were studied. The PCR-RFLP method was used for genotyping rs12255372 (G/T) polymorphism, and the SPSS version 18.0 for Windows for statistical analysis. The minor T allele of TCF7L2 rs12255372 was found to significantly increase the risk of T2DM, with an allelic odds ratio (OR) of 1.458 (95% CI 1.108–1.918, p = 0.007). A significant difference in TT genotype was observed between T2DM patients and normoglycemic controls (OR 2.038, 95% CI 1.147–3.623; p = 0.014). On assuming dominant and recessive models, ORs of 1.52 [95% CI (1.05–2.21) p = 0.026)] and 1.74 [95% CI (1.01–3.00) p = 0.043] were obtained, respectively, thereby implying that the co-dominant model would best fit the susceptible gene effect. This study further confirms the TCF7L2 gene as enhancing susceptibility to the development of T2DM.

Highlights

Type 2 diabetes mellitus (T2DM) is a heterogeneous metabolic disorder arising from the interplay of genetic and environmental factors (Barroso, 2005)
The minor T allele of the transcription factor 7–like gene (TCF7L2) rs12255372 was found to significantly increase T2DM risk, with an allelic odds ratio (OR) of 1.458 in the population under study
A comparison of genotype frequencies in T2DM patients and normoglycemic controls showed a significant difference in the frequency of the TT genotype, not so in the GG and GT genotypes (Table 1)

Summary

Introduction

Type 2 diabetes mellitus (T2DM) is a heterogeneous metabolic disorder arising from the interplay of genetic and environmental factors (Barroso, 2005). The aim was to investigate the association between the TCF7L2 rs12255372 variant and T2DM in an Iranian population. The studied population comprised 236 unrelated T2DM patients and 255 normoglycemic controls without diabetes.

Results

Conclusion