The rs3737964 single‐nucleotide polymorphism of the chloride channel‐6 gene as a risk factor for coronary heart disease

The present study investigates the association of single-nucleotide polymorphisms (SNPs) on the chloride channel-6 (CLC-6) gene with coronary heart disease (CHD) in China. We carried out a large case-control study among 1193 CHD patients and 1200 unrelated healthy control subjects. Information on the participants' health status was collected through the modified Inter-heart questionnaire. Genomic DNA from peripheral blood samples was analyzed for the genotypes of rs3737964 and rs3737965 SNPs on the CLC-6 gene using Taqman probe-based quantitative real-time PCR (qPCR). We compared the collected data between the case group and the control group by chi-square test and t/nonparametric test. Furthermore, we performed logistic regression to evaluate factors associated with CHD. The frequency of TT genotypes in rs3737964 was significantly higher in CHD patients compared to the control group, with an odds ratio (OR) of 2.32 (95% confidence interval, CI: 1.17-4.06, P = 0.016). The association of CHD with TT genotype was even stronger in smoking population after adjusting for confounders (OR = 3.19, 95% CI: 1.04-9.79, P = 0.043). Multivariate logistic regression showed the CHD risk associated with TT genotype in rs3737964 was particularly among population who were more than 60 years old, smoking, and male (P = 0.023, 0.008 and 0.043, respectively). The present study has revealed that rs3737964 SNP of CLC-6 was associated with CHD. In particular, subjects with TT genotype who were 60-plus years old, with smoking habit or were male were more susceptible to CHD.