Introduction:
Interleukin-17A (IL-17A), a pro-inflammatory cytokine, plays an important role in the pathogenesis of asthma. A number of studies have investigated the relationship between IL-17A rs2275913 polymorphism and risk of asthma. However, the results obtained are inconclusive. The aim of this meta-analysis is to clarify the relationship between IL-17A rs2275913 polymorphism and asthma risk.

Material and methods:
Searches were conducted in PubMed, Web of Science, Elsevier, Google Scholar, Wanfang and Chinese National Knowledge Infrastructure (CNKI) databases, and data were extracted from eligible studies by two independent reviewers. The pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated. Publication bias, heterogeneity and sensitivity analysis were also assessed.

Results:
Ten studies with a total of 5016 subjects were included. Overall, the results indicated a significant association between the IL-17A rs2275913 polymorphism and the risk of asthma (G vs. A: OR = 0.866, 95% CI = 0.789–0.951, p = 0.003; GG+GA vs. AA: OR = 0.752, 95% CI = 0.633–0.895, p = 0.001). In subgroup analysis by age and ethnicity, the G allele of rs2275913 in IL-17A was significantly associated with a reduced risk of asthma in children and Asians.

Conclusions:
The results of this meta-analysis indicate that the G allele of rs2275913 in IL-17A is a protective factor for the development of asthma.