Interleukin 12B gene polymorphisms and susceptibility to rheumatoid arthritis: a data synthesis.

The aim of this study was to investigate the association of two common interleukin 12B (IL-12B) polymorphisms (rs3212227 and rs6887695) with rheumatoid arthritis (RA) susceptibility through meta-analyses. A systematic literature search of PubMed, Web of Science, Cochrane Library, and Embase databases was conducted on articles published before 28 February 2016. Then odds ratio (OR) with 95 % confidence interval (CI) was used to quantify the strength of association for homozygote, heterozygote, dominant, and recessive genetic models. Nine articles with a total of 17 case-control studies (12 for IL-12B rs3212227 polymorphism and 5 for IL-12B rs6887695 polymorphism) met our inclusion criteria. The pooled results demonstrated that IL-12B rs3212227 (homozygote model: OR = 0.96, 95 % CI = 0.81-1.15; heterozygote model: OR = 1.07, 95 % CI = 0.93-1.23; dominant model: OR = 1.05, 95 % CI = 0.91-1.20; recessive model: OR = 0.93, 95 % CI = 0.79-1.10) and rs6887695 (homozygote model: OR = 1.01, 95 % CI = 0.84-1.21; heterozygote model: OR = 1.14, 95 % CI = 0.86-1.51; dominant model: OR = 1.14, 95 % CI = 0.87-1.48; recessive model: OR = 1.01, 95 % CI = 0.85-1.21) polymorphisms may not be associated with RA risk. Our meta-analyses demonstrated that IL-12B rs3212227 and rs6887695 polymorphisms do not confer susceptibility to RA.