KCNQ1 and type 2 diabetes: study in Hubei Han Chinese and meta-analysis in East Asian populations

Recent genome-wide association studies in East Asian poulations reported the association of KCNQ1 variants with type 2 diabetes. In the present study, we first investigated the association between rs2237892 in KCNQ1 and type 2 diabetes in a Hubei Han Chinese population (223 type 2 diabetes patients and 201 controls). The frequencies of CC genotype and C allele in type 2 diabetes patients were significantly higher than those of controls group (CC: 51.6% vs 39.3%, P=0.001; C: 72.2% vs 61.2%, P=0.001). The odds ratio for the risk allele C was 1.65 (95%CI 1.23–2.2, P=0.001). Then, we systematically reviewed the association of SNPs (rs2237892, rs2237895, rs2237897, rs2074196) in KCNQ1 with type 2 diabetes risk in a meta-analysis. Significant heterogeneity between studies was found for SNPs rs2237892 and rs2237897. Combined odds ratios of the rs2237892 C, rs2237895 C, rs2237897 C, rs2074196 G allele were 1.35 (95% CI 1.29–1.41, P<0.0001), 1.27 (95%CI 1.23–1.32, P<0.0001), 1.32 (95%CI 1.21–1.43, P<0.0001), 1.30 (95%CI 1.25–1.35, P<0.0001) respectively. Our results and meta-analysis demonstrated that KCNQ1 polymorphisms were reproducibly associated with the risk of type 2 diabetes in Han Chinese and East Asian populations.