Interleukin-10 Promoter 1082/−819/−592 Polymorphisms are Associated with Asthma Susceptibility in Asians and Atopic Asthma: A Meta-Analysis

Background Although interleukin-10 (IL-10) is a potent inhibitor of allergic diseases, the association between promoter −1082/−819/−592 polymorphisms and asthma susceptibility remains inconclusive. We sought to determine if IL-10 promoter −1082/−819/−592 polymorphisms contribute to asthma susceptibility and are associated with phenotypes of atopic asthma. Methods Systematic computerized searches were performed. Pooled odds ratios (ORs) and 95 % confidence intervals (CIs) were estimated by using random-effect and fixed-effect models, based on between-study heterogeneity. Subgroup analyses were performed according to age, ethnicity, and atopy. Publication bias was detected by funnel plot using Egger’s test. Results A total of 4,716 asthmatic patients and 5,093 controls were included. The asthma susceptibility correlated significantly with IL-10 promoter gene −1082 polymorphism [OR (95 % CI) 1.26 (1.02, 1.55) for AA vs. AG + GG] and −592 polymorphism [OR (95 % CI) 1.12 (1.07, 1.34) for AC + AA vs. CC] (both P 0.05). Subgroup analyzes suggested that the AA versus AG + GG genotype of −1082A/G polymorphism and AC + AA versus CC genotype of −592A/C polymorphism contributed significantly to increased asthma susceptibility in adults [OR (95 % CI) 1.39 (1.03, 1.87) for −1082A/G and 1.53 (1.25, 1.87) for −592A/C polymorphism]. The Asian population [OR (95 % CI) 1.35 (1.1, 1.7) for −1082A/G and 1.4 (1.12, 1.64) for −592A/C polymorphism] and subjects with atopic asthma [OR (95 % CI) 1.49 (1.18, 1.88) for −1082A/G and 1.23 (1.01, 1.48) for −592A/C polymorphism] also had an increased susceptibility of asthma. No publication bias was detected. Conclusions IL-10 promoter −1028A/G, −592A/C polymorphisms and their haplotypes, but not −819T/C polymorphism, correlate with asthma susceptibility.