Interleukin-12B gene polymorphisms and bronchial asthma risk: A meta-analysis

Objective: This meta-analysis aims to investigate whether interleukin-12B (IL-12B) -1188A/C or the promoter polymorphisms may be a risk factor for asthma. Data Sources: Web of Science, PubMed, China National Knowledge Infrastructure (CNKI) and Wanfang databases were searched (updated August 20, 2015). Study selections: Articles evaluating the association between IL-12B genetic polymorphisms and asthma risk were selected. Results: 13 eligible studies with a total of 5092 subjects were finally included in this meta-analysis. For IL-12B -1188A/C, analysis by ethnicity indicated that there was a markedly reduced risk for asthma in East Asian (CC + AC vs. AA: OR = 0.64, 95% CI = 0.50-0.81, P < 0.001). For IL-12B promoter, analysis by ethnicity indicated there was a markedly increased risk in East Asian (MM vs. WM + WW: OR = 1.57, 95% CI = 1.18-2.10, P = 0.002). Analysis by allergic state revealed the similar results in atopic subgroup. Conclusions: IL-12B -1188 C allele may be a protective factor against asthma in East Asian. In addition, promoter MM genotype may be a risk factor for asthma in East Asian and allergic people.