Correlation study on ß2-adrenergic receptor gene polymorphisms and asthma susceptibility: evidence based on 57 case-control studies.

ABSTRACT

OBJECTIVE: Previous studies have indicated that ß2-adrenergic receptor (ADRB2) genetic polymorphism is related to the risk of asthma, but the results still have some controversy and uncertainty. To this end, the meta-analysis was performed, including all studies that can be used to assess the correlation between ADRB2 polymorphism and asthma susceptibility. MATERIALS AND METHODS: The related papers on ADRB2 polymorphisms and asthma were systematically reviewed in databases of PubMed, EMBASE, Cochrane Library, and WanFang, Odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were measured. The sensitivity analysis and publication bias were evaluated to investigate the correlation. RESULTS: This meta-analysis included 57 papers in total involving 11,157 cases and 12,281 controls. Results illustrated that the C79G variant genotypes owned a reduced effect on asthma susceptibility (G vs. C OR=0.94, p=0.037). In the age stratification analysis, C79G polymorphism owned a reduced effect on asthma risk for children (GG vs. CC OR=0.69, p=0.002; GG vs. CC+CG OR=0.65, p<0.001). Furthermore, in the ethnic stratification analysis, the C79G variant genotypes also owned a reduced effect on asthma in Asians (GG vs. CC OR=0.80, p=0.027; GG vs. CC+CG OR=0.81, p=0.02). Besides, for A46G polymorphism, the ethnic stratification analysis demonstrated that the A46G variant owned an increased effect on asthma susceptibility among Caucasians (G vs. A OR=1.15, p=0.043). For C491T polymorphism, a considerable reduced effect was found between C491T and asthma susceptibility for children (CT vs. CC OR=0.70, p=0.03). In the ethnic stratification analysis, the effect was also considerable in the Caucasian subjects. CONCLUSIONS: The present meta-analysis demonstrated that C79G and C491T polymorphism may be a defensive factor for asthma, while A46G polymorphism may be a risk factor for asthma among the Caucasian population.