Association of resistin gene 3'UTR+62G>A polymorphism with insulin resistance, adiposity and the adiponectin-resistin index in Mexican population

Abstract

Insulin resistance (IR) is a disease with genetic susceptibility characterized by the increase in storage and irregular body fat distribution, and impaired production of adipokines. The objective was to investigate the relationship between 3'UTR+62G>A RETN gene polymorphism, with adiponectin-resistin index (ARindex), adiposity, and inmuno-metabolic markers. In this cross-sectional study, 260 individuals characterized as Mexican-Mestizo and classified in lean and overweight, and IR and without-IR, were included. Anthropometrics, body composition, body fat distribution and inflammation and metabolic markers were measured by routine methods, RETN 3'UTR+62G>A alleles were identified by PCR-RFLP and soluble insulin, total adiponectin and resistin were measured by ELISA methods. The +62G allele frequencies for lean and overweight individuals were different P=0.0343 (95.4% and 98.4%, respectively). The lean GA genotype carriers showed significant low measures of ARindex, adiposity, and inmuno-metabolic markers, than the GG genotype carriers. We found differences between individuals with IR and without-IR: in ARindex (P=0.002), adiponectin (P=0.002) and resistin levels (P=0.033): 1.102 ± 0.03, 5.167 ± 0.36 ug/mL and 8.827 ± 0.42 ng/mL versus 1.336 ± 0.07, 3.577 ± 0.34 ug/mL and 10.480 ± 0.65 ng/mL. Showed correlations with inflammation markers, distribution and body fat storage (r=0.262 to 0.414), P< 0.05. The present data suggest that in a Mexican-mestizo population the RETN +62G>A polymorphism is associated with overweight. The presence of the +62A allele was associated with increase of total adiponectin, ARindex, resistin levels, metabolic markers and body fat storage. ARindex can be an early indicator of insulin resistance.