Role of eNOS and TGFβ1 gene polymorphisms in the development of diabetic nephropathy in type 2 diabetic patients in South Indian population

Background: Diabetic nephropathy is known to be a leading complication of diabetes mellitus, characterized by diverse aspects such as high urinary albumin level, elevated blood pressure, and genetic susceptibility leading to end-stage renal disease. The current study was carried out to investigate the association of eNOS and TGF beta 1 gene polymorphisms in the progression of diabetic nephropathy among type 2 diabetic patients in the South Indian population. The eNOS and TGF beta 1 genetic variants were genotyped in 280 T2DM patients, 140 with DN, 140 without DN, and 140 controls. Genotyping was performed using ARMS PCR and the genomic variants were confirmed by the Sanger sequencing method. Results: A significant (p < 0.05) association was observed in the genotypic frequencies of eNOS (G > T) polymorphism in the T2DM patients with diabetic nephropathy when compared to controls. The frequency of TT (heterozygous) genotype was observed to increase in patients with type 2 diabetes and DN when compared to the diabetic patients without DN and controls. This indicates that diabetic patients with TT genotype are at an increased risk to develop DN. However, TGF beta 1 (G > C) polymorphism did not show any association in the allele and genotypic frequencies with DN when compared with T2DM and controls. Conclusion: The results of the study propose a strong influence of TT genotype of eNOS gene be significantly linked with diabetic nephropathy in T2DM patients. Whereas no association was examined concerning TGF beta 1 gene polymorphism and DN. Nevertheless, large sample size studies are required to confirm the part of these genetic variants in the development of DN.