Sanger Sequencing Reveals Novel Variants in , , and Genes in Patients of Early and Severe Diabetic Nephropathy.

Diabetes is a global health issue, with approximately 50% of patients developing diabetic nephropathy (DN) and 25% experiencing early and severe forms of the disease. The genetic factors contributing to rapid disease progression in a subset of these patients are unclear. This study investigates genetic variations in the , , and genes associated with early and severe DN. Sanger DNA sequencing of the exons of , , and genes was conducted in 113 patients with early and severe DN (defined as occurring within 10 years of the diagnosis of diabetes and with eGFR < 45 mL/min/1.73 m) and 100 controls. The impact of identified genetic variations was analyzed using computational protein models created in silico with SWISS-Model and SWISS-Dock for ligand binding interactions. In , two heterozygous missense mutations, c.102G>T and c.147C>G, and one heterozygous nonsense mutation, c.148G>T, were identified in patients. The SNP rs1049346 (G>A) at location 6:38703061 (GRCh38) was clinically significant. The c.147C>G mutation (C19S) was associated with ligand binding disruption in the GLO1 protein, while the nonsense mutation resulted in a truncated, non-functional protein. In , two heterozygous variations, one missense c.358G>A, and one silent mutation c.311G>C were observed, with the former (D120N) affecting the active site. No significant changes were noted in gene variants concerning protein structure or function. The study identifies four novel and five recurrent mutations/polymorphisms in , , and genes associated with severe DN in Pakistani patients. Notably, a nonsense mutation in led to a truncated, non-functional protein, while missense mutations in and potentially disrupt enzyme function, possibly accelerating DN progression.