No abstract

Aims/hypothesis Two recent genome-wide association studies have identified several novel type 2 diabetes susceptibility variants in intron 15 of the KCNQ1 gene. We aimed to evaluate the effects of the variants in KCNQ1 on type 2 diabetes and metabolic traits in the population of mainland China. Methods Three candidate single nucleotide polymorphisms were genotyped in 1,912 individuals with type 2 diabetes and 2,041 normal controls using the ligase detection reaction method.Results We confirmed the association of KCNQ1 with type 2 diabetes in the population of mainland China. Allele frequency ORs of the three single nucleotide polymorphisms (SNPs) were: rs2237892 (OR 1.19, 95% CI 1.08-1.31, p = 3.0 × 10 −4 ); rs2237895 (OR 1.20, 95% CI 1.09-1.32, p=1.9×10 −4 ); and rs2237897 (OR 1.24, 95% CI 1.13-1.36, p= 3.9×10 −5 ). We also found a significant difference in the distribution of the global haplotypes between the type 2 diabetes group and the normal control group (p= 2.6×10 −5 ). In addition, in the control group SNP rs2237892 was marginally associated with increasing fasting plasma glucose and SNPs rs2237892 and rs2237897 were associated with HbA 1c . Furthermore, for all three variants, homozygous carriers of the diabetes-associated allele had significantly decreased BMI and waist circumferences. Conclusions/interpretation Our investigation confirmed the effects of KCNQ1 variants on type 2 diabetes risk in the Chinese population.