Association of adiponectin gene polymorphisms and their haplotypes with type 2 diabetes and related metabolic traits in an Iranian population

Abstract

Adiponectin is an adipocyte-secreted protein that contributes to glucose homeostasis. Contradictory reports are available on single nucleotide polymorphisms (SNPs) in the adiponectin gene and the risk of type 2 diabetes (T2D). We investigate the association of adiponectin gene SNPs (+45T/G and +276G/T) with serum adiponectin, insulin resistance, lipid profile, and T2D risk in an Iranian population. The +45T/G and +276G/T SNPs were genotyped in 211 non-familial T2D patients and 202 non-diabetic subjects by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and TaqMan probe, respectively. T2D was associated with a decrease in serum adiponectin level. The G allele and the GG and TG genotypes of +45T/G SNP were more abundant than the T allele and the TT genotype in T2D patients compared with controls (p < 0.001). The risk of T2D in individuals with the GG and TG genotypes of +45T/G SNP was 4 and 2 times more than that with the TT genotype, respectively. There was no statistically significant difference in the frequencies of allele and genotype of +276G/T SNP between the control and T2D groups. The presence of +45G/+276G haplotype was associated with an increased risk of T2D (OR = 2.01, 95% CI = 1.34–3.03, p = 0.04). Therefore, our results showed that +45T/G SNP is associated with the risk of T2D higher than +276G/T SNP in the studied population.