TCF7L2 gene polymorphism as a risk for type 2 diabetes mellitus and diabetic microvascular complications

Type 2 Diabetes Mellitus (T2DM) is a chronic metabolic condition with various genetics and environmental influences that affects the capacity of the body to produce or use insulin resulting in hyperglycemia, which may lead to variable complications. It is one of the world's rising health problems. There is emerging evidence that some genetic polymorphisms can impact the risk of evolving T2DM. We try to determine the relationship of (rs7903146) variant of the Transcription factor 7-like 2 (TCF7L2) gene with T2DM and its microvascular complications.

This case-control study included 180 subjects: 60 diabetic patients without complications, 60 diabetic patients with microvascular complications and 60 matched healthy controls. Genotypes of rs7903146 (C/T) SNP in the TCF7L2 gene were evaluated by real-time polymerase chain reaction via TaqMan allelic discrimination. Logistic regression was used to detect the most independent factor for development of diabetes and diabetic microvascular complications. Variant homozygous TT and heterozygous CT genotypes were significantly increased in diabetic without complications and diabetic with complications groups than controls (p = 0.003, 0.001) respectively. The T allele was more represented in both patient groups than controls with no significant difference between patient groups. TT genotype as well as T allele was significantly associated with increased T2DM risk.

The T allele of rs7903146 polymorphism of TCF7L2 confers susceptibility to development of T2DM. However, no significant association was found for diabetic complications.