RESUMEN
OBJECTIVE: Diabetic nephropathy (DN) remains the most common cause of end stage renal disease (ESRD) as the burden of diabetes increases worldwide. Only 25 to 40% of patients with type 2 diabetes mellitus (T2DM) develop diabetic nephropathy irrespective of glycemic control so there should be a specific genetic basis for the development of diabetic nephropathy. METHODS: We have collected venous blood samples from 50 cases (Diabetic nephropathy) and 20 controls (T2DM without nephropathy) diagnosed by spot urine albumin creatinine ratio (ACR). DNA was isolated from processed samples. PCR study and sequencing was done to detect polymorphism of rs2237897 in KCNQ1 gene. RESULTS: Statistically significant difference was found when the allelic frequencies between the two groups were compared (p=0.03), with the C allele having a 2.4 fold higher risk of having diabetic nephropathy (risk ratio, RR )= 1.16, 95%CI of RR = 1.01 to 1.3, Odds Ratio (OR) =2.4; 95% CI of OR =1.06 to 4.6). Chi-square analysis showed a significant difference in genotype frequency of rs2237897 (χ2 = 4.63, p=0.03) in Diabetic nephropathy subjects, compared with that of controls. CONCLUSIONS: This study suggested that, KCNQ1 being an established type 2 diabetes gene, genetic variation in this gene may contribute to susceptibility to diabetic nephropathy and the C allele is the risk allele for diabetic nephropathy, which is different from Japanese population where the T allele was the risk allele.