Purpose: Recently, the roles of TIM-1 genetic polymorphisms in asthma have been extensively studied, with conflicting results. Therefore, we performed the present meta-analysis to better assess potential associations of TIM-1 genetic polymorphisms with asthma.
Methods: Eligible articles were searched in PubMed, Medline, EMBASE, Google Scholar, and CNKI up to December 2016. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to detect any potential associations between TIM-1 genetic polymorphisms and asthma.
Results: A total of 12 articles including 3120 asthma patients and 2825 control subjects were analyzed. The overall and subgroup analyses revealed that TIM-1-416G>C single nucleotide polymorphism was significantly associated with asthma for the Asian population in the codominant (G/G vs. G/C, p = 0.0003, OR 1.86, 95% CI 1.33-2.60) and dominant (G/G vs. G/C + C/C, p < 0.0001, OR 1.94, 95% CI 1.40-2.69) genetic models. Nevertheless, we failed to detect any significant associations between TIM-1-416G>C single nucleotide polymorphism and asthma in Caucasians. Additionally, according to our analyses, TIM-1 5383_5397 insertion/deletion polymorphism was not correlated with asthma in both Asians and Caucasians.
Conclusions: In conclusion, our findings suggest that TIM-1-416G>C single nucleotide polymorphism is associated with asthma susceptibility for the Asian ethnicity in certain genetic models. However, TIM-1 5383_5397 insertion/deletion polymorphism may not be correlated with the risk of asthma.
Keywords: Asthma; Genetic polymorphisms; Meta-analysis; T cell immunoglobulin domain and mucin domain-1 (TIM-1).