Background: Apelin is an adipokine that contributes to the pathogenesis of type 2 diabetes. The plasma levels of apelin increased in obese patients and diabetic subjects. This study aimed to investigate the effects of apelin genetic variants on type 2 diabetes and related quantitative traits.
Methods: We selected three single nucleotide polymorphisms (SNPs) that could capture all common variants in APLN gene region and genotyped them in 1892 type 2 diabetic patients and 1808 normal glucose regulation controls. The clinical features related to glucose metabolism were measured in the controls. The comparison of allele and genotype distribution in the cases and controls were performed by using chi(2) tests. The association between SNPs and quantitative traits were analyzed using Wilcoxon's rank-sum test.
Results: None of the SNPs or haplotypes showed evidence of association to type 2 diabetes. However, rs2235306 was nominally associated with fasting plasma glucose levels in the male subjects with normal glucose regulation ((4.93 +/- 0.03) vs (5.01 +/- 0.03) mmol/L, P = 0.04). No significant difference was observed between all three SNPs and other variables.
Conclusions: APLN SNP rs2235306 was associated with fasting plasma glucose levels in males. It suggests that APLN genetic variants may contribute to clinical features related to glucose metabolism in Chinese population.