Association between interleukin-17a gene polymorphisms and asthma risk: a meta-analysis

Area of Science:

• Genetics and Immunology
• Respiratory Medicine

Background:

• Interleukin-17A (IL-17A) is a proinflammatory cytokine implicated in asthma pathogenesis.
• Previous studies on IL-17A polymorphisms and asthma risk have yielded inconsistent findings.

Purpose of the Study:

• To conduct a meta-analysis for a precise estimation of the association between IL-17A gene polymorphisms and asthma risk.
• To clarify the role of specific IL-17A polymorphisms in asthma susceptibility.

Main Methods:

• Systematic search of multiple databases (PUBMED, MEDLINE, EMBASE, CNKI, Wan Fang) up to December 12, 2014.
• Inclusion of seven case-control studies with 2882 asthma patients and 2093 healthy controls.
• Meta-analysis, subgroup, sensitivity, and publication bias analyses performed using Stata 12.1 software.

Main Results:

• The IL-17A -737C/T polymorphism demonstrated a significant protective effect against asthma across allele, dominant, and heterozygous models (P = 0.007, P < 0.001, P < 0.001, respectively).
• This protective association for IL-17A -737C/T was consistent in subgroup analyses stratified by ethnicity (Asian populations) and age (children).
• No significant association was found between the IL-17A -197G/A polymorphism and asthma risk in overall or subgroup analyses.

Conclusions:

• The IL-17A -737C/T polymorphism is likely a protective factor against asthma development.
• The IL-17A -197G/A polymorphism does not appear to be significantly associated with asthma susceptibility.
• Further research may be warranted to fully elucidate the genetic contributions to asthma.