Association of the +33371 A/G polymorphism in adiponectin receptor 2 gene with Type 2 diabetes in the Chinese population

Purpose: The aim of this study was to investigate the association between the +33371 A/G polymorphism of adiponectin receptor 2 gene and the risk of Type 2 diabetes (T2DM) in the Chinese population. Methods: A case-control study was performed among 594 unrelated Chinese people. All of them underwent a standardized assessment on phenotypic characterization including anthropometry, 75-g oral glucose tolerance test with insulin levels, fasting serum total cholesterol, and fasting serum triglyceride. The +33371 A/G polymorphism was detected by PCR-restriction fragment length polymorphism. Results: The PCR products after digestion displayed 3 genotypes, including AA, AG, and GG. The frequencies of AA, AG, and GG genotypes in T2DM group (no.=261) and control group (no.=353) were 0.379, 0.414, 0.207 and 0.162, 0.541, 0.297, respectively. There was a significant difference in both genotypic and allelic frequencies distribution of +33371 A/G polymorphism between T2DM and control subjects (p<0.001). Subjects with AA+AG genotypes showed higher levels of fasting plasma glucose (p=0.024), fasting serum triglycerides (p=0.036), and body mass index (BMI) (p=0.013) than those with GG genotype in the T2DM group but not in the control group. Compared with GG genotype, AA (p<0.001) and AA+AG (p=0.002) genotype group had a significantly higher risk of T2DM, with odds ratio (OR) for 2.290 [95% confidence interval: 1.482–3.359] and 1.963 (1.183–2.997). Compared with AG+GG genotype group, the risk of T2DM in AA genotype increased slightly (p=0.007), with OR for 1.478 (1.025–2.036). Conclusion: The present findings suggest that +33371 A/G polymorphism is associated with increased risk of T2DM and multiple insulin resistance-related phenotypes (including fasting plasma glucose, fasting serum triglycerides, and BMI) in the Chinese population.