A comprehensive meta-analysis comprising 149 case-control studies to investigate the association between IL-6 gene rs1800795 polymorphism and multiple disease risk

Abstract

Background: Individual genome-wide association studies (GWAS) or single case-specific meta-analyses may not be sufficient evidence to take action against a specific gene function. Thus, we tried to determine a consensus association between the IL-6 gene rs1800795 polymorphism and multiple disease risks through an updated statistical meta-analysis.

Method: After systematically searching online databases, we found 149 case-control relevant datasets with a sample size of 96,153 (cases: 38,291 and controls: 57862) and conducted the meta-analysis using updated statistical models.

Results: The analyses of this comprehensive meta-analysis revealed a significant association between IL-6 -174G/C polymorphism and overall disorder risk under all genetic models (C vs G: OR = 1.11, 95% CI = 1.08-1.13; p-value = 4.8E-17; CC vs GG: OR = 1.19, 95% CI = 1.13-1.26; p-value = 9.4E-12; CG vs GG: OR = 1.10, 95% CI = 1.06-1.14; p-value = 1.1E-07; CC + CG vs GG: OR = 1.13, 95% CI = 1.10-1.17; p-value = 1.1E-13; CC vs CG + GG: OR = 1.18, 95% CI = 1.06-1.31; p-value = 0.0019) and (OR > 1) with Asian ethnicity. The subgroup analyses based on the diseases revealed that the polymorphism was highly significantly increasing the risk of coronary artery disease (CAD) under all genetic models. Likewise, a significant association was observed with increased risk under three genetic models of inflammatory diseases (C vs G; CC vs GG; and CC vs CG + GG), and rheumatoid arthritis (C vs G; CG vs GG; and CC + CG vs GG). Conversely, the -174G/C SNP significantly decreased the risk of ischemic stroke under the two genetic models (C vs G; and CG vs GG). However, the other diseases included in this study showed no significant association with IL-6 (-174G/C) polymorphism.

Conclusion: This meta-analysis provided strong evidence for the association between IL-6 gene rs1800795 polymorphism and multiple disease risks. The IL-6 gene could be a useful prognostic biomarker for CAD, inflammatory disease, ischemic stroke, and rheumatoid arthritis.

Keywords: CAD; Diseases; IL-6; Inflammatory disease; Ischemic stroke; Meta-analysis; Rheumatoid arthritis; SNPs; rs1800795.