The Association of Transcription Factor 7 like 2 Gene Polymorphism with Diabetic Nephropathy in Patients with Type 2 Diabetes Mellitus

Background: The exact relationship between the different TCF7L2 gene polymorphisms and the development of diabetic nephropathy (DN) remains unclear. Objective: To investigate the association of TCF7L2 rs12255372 (G/T) gene polymorphism and diabetic nephropathy (DN) in patients with type 2 diabetes (T2D). Methods: 100 patients with T2D (50 patients without DN and 50 patients with DN) and 50 age and sex-matched healthy controls (HC) were enrolled in the study. Genotyping for the rs12255372 (G>T) polymorphism in the TCF7L2 gene was performed by real-time PCR. Results: The rs12255372 polymorphism showed a statistically significant difference between HC and patients with and without DN in both the genotype and allele frequency. However, the rs12255372 polymorphism genotype or allele frequency was not statistically different between patients with DN and those patients without DN. The G allele was found to be higher in patients and the T allele was higher in HC suggesting that the G allele was the risk allele for developing T2D & DN and that the T allele was protective. Conclusion: rs12255372 TCF7L2 gene polymorphism was strongly associated with type 2 diabetes mellitus and DN. The association between rs12255372 polymorphism and DN was a mere reflection of a complicated diabetes mellitus rather than a direct independent association.