SUMO4 163 G>A variation is associated with kidney disease in Indian subjects with type 2 diabetes.

Genetic susceptibility probably plays a role in the development and/or progression of diabetic kidney disease. Small ubiquitin-related modifier 4 (SUMO4) mRNA is expressed in human kidney. Substitution of methionine with valine at codon 55 (M55V) of SUMO4 gene induces higher nuclear factor-kB activity, which is known to mediate the development of kidney disease in individuals with diabetes. We investigated the association between the SUMO4 M55V (rs237025, c.163 G>A) and kidney disease in north Indian subjects with diabetes. A case-control analysis was performed using genomic DNA samples from 216 diabetic patients without nephropathy (DM) and 201 diabetic with nephropathy (DN). The SUMO4 c.163 G>A polymorphism was genotyped using polymerase chain reaction amplification followed by restriction digestion. The duration of diabetes was significantly greater in DN. The genotypic and allelic frequencies were different in DM and DN groups: GG genotype was significantly more frequent in DN as compared to DM (p = 0.018, OR 1.72, 95% CI 1.1-2.7). Similarly the G allele was more frequent in DN compared to DM (p = 0.017, OR 1.4, 95% CI 1.1-1.8). This study suggests that SUMO4 c.163 G>A polymorphism is associated with the susceptibility to diabetic nephropathy in north Indian subjects with type 2 diabetes.