Investigating the distribution of TCF7L2 (rs7903146) gene polymorphism in type 2 diabetic patients in West of Iran Mazandaran

Type 2 diabetes mellitus is a complex heterogeneous group of metabolic conditions characterized by increased levels of blood glucose due to impairment in insulin action and/or insulin secretion. The TCF7L2 gene is considered as one of the major genes susceptible to diabetes.The single nucleotide polymorphism rs7903146 is located in intron 3 of this gene, which is significantly effective in type 2 diabetes. In this case-control study, 141 patients and 86 healthy subjects were present. 5cc peripheral blood of diabetics was collected in EDTA-containing tubes. Genomic DNA was extracted using salting-out method and polymorphism genotype was investigated using PCR-RFLP method. Genotype and allele frequencies of the rs7903146 polymorphism differed significantly between type 2 diabetic patients and non-diabetic subjects (P = 0.0468 and P = 0.0474 , respectively). The frequency of T allele was 54.5% in type 2 diabetes group and 39.5% in non-diabetic subjects, and this allele was significantly associated with type 2 diabetes risk (OR = 1.8333, 95% CI 1.0456 – 3.2144). Our results confirmed the association between the rs7903146 polymorphism of the TCF7L2 gene and the increased risk of type 2 diabetes in the west-Mazandaran, Iran.