Genetic polymorphisms of interleukin-6 gene and susceptibility to coronary artery disease in Chinese population: Evidence based on 4582 subjects

The aim of this study was to explore whether interleukin-6 (IL-6) gene (?174 G/C and ?572 C/G) polymorphisms are associated with susceptibility to coronary artery disease (CAD) risk in Chinese population. All the statistical tests were performed using Stata version 11.0. Twelve articles involving 16 studies were included in this meta-analysis, covering a total of 2309 CAD cases and 2273 controls. For IL-6 gene ?572 C/G polymorphism, the results showed evidence for significant association between IL-6 gene ?572 C/G polymorphism and CAD risk (for G allele vs. C allele: OR = 1.48, 95% CI = 1.26–1.74, p < 0.001; for G/G vs. C/C: OR = 2.60, 95% CI = 1.54–4.39, p < 0.001; for G/G vs. G/C + C/C: OR = 2.15, 95% CI = 1.35–3.42, p = 0.001; for G/G + G/C vs. C/C: OR = 1.55, 95% CI = 1.29–1.85, p < 0.001). However, for IL-6 gene ?174 G/C polymorphism, no significant association was found between this variation and CAD risk. In summary, our meta-analysis showed evidence that IL-6 gene ?572 C/G polymorphism may be a risk factor for CAD susceptibility. For IL-6 gene ?174 G/C polymorphism, no significant association was found between this variation and CAD risk.