Interactions between () gene and gene and environment factors on coronary heart disease risk in a Chinese Han population.

AIMS

To investigate the association of several single nucleotide polymorphisms (SNPs) within Interleukin-6 () and vitamin D receptor () gene, and additional gene- gene and gene- smoking interaction with coronary heart disease (CHD) risk in a Chinese population.

METHODS

Hardy-Weinberg equilibrium (HWE) examination was used by SNPstats (http://bioinfo.iconcologia.net/SNPstats). Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combination among SNPs and smoking. Stratified analysis for gene- smoking interaction was investigated by logistic regression.

RESULTS

CHD risk was significantly higher in carriers with the C allele of rs1800796 within gene than those with GG genotype (GC+ CC versus GG), adjusted OR (95%CI) =1.62 (1.19-2.23); CHD risk was also higher in carriers with the T allele of rs2228570 within gene than those with CC genotype (CT+ TT versus CC), adjusted OR (95%CI) = 1.68 (1.26-2.17). However, we did not find any direct associations of the others SNPs in and gene with CHD risk. We also found a significant interaction between rs1800796 and smoking, the cross-validation consistency of this two- locus model was 10/ 10, and the testing accuracy was 60.11%. Current smokers with rs1800796- GC or CC genotype have the highest CHD risk, compared to never- smokers with rs1800796- GG genotype within gene, OR (95%CI) = 2.57 (1.74 -3.46).

CONCLUSIONS

We found that the C allele of rs1800796 within and T allele of rs2228570 within gene, interaction between rs1800796 and smoking were all associated with increased CHD risk.