Association of 45-bp ins/del polymorphism of uncoupling protein 2 (UCP2) and susceptibility to nonalcoholic fatty liver and type 2 diabetes mellitus in North-west of Iran

OBJECTIVE: Uncoupling protein 2 (UCP2) plays a crucial role in energy homeostasis via insulin secretion regulation, free fatty acid concentrations, and lipid metabolism. This study aimed to investigate the association of 45-bp ins/del polymorphism of UCP2 with susceptibility to NAFLD (Non-Alcoholic Fatty Liver Disease) and T2DM (Type 2 Diabetes Mellitus). DNA was extracted from the white blood cells of the subjects, and the gene polymorphism was determined using polymerase chain reaction (PCR). In this study, 72 patients with NAFLD, 71 healthy individuals as control, 80 patients with T2DM, and 77 healthy controls were enrolled in the study. RESULTS: A higher prevalence of insertion/insertion genotype was observed in T2DM patients compared to the controls (p- value˂ 0.05). There was no difference in genotype distribution between NAFLD patients and controls (p-value > 0.05). NAFLD patients with D/D, D/I genotype had higher triglyceride, ALT, and AST levels; however, their HDL levels were lower than healthy controls. Patients with T2DM with D/D or D/I genotype also had significantly higher fasting serum glucose (FSG). While we found an association between the 45 bp I/D polymorphism in 3ʹUTR of UCP2 and T2DM, no correlation between this polymorphism and NAFLD was identified.