Arg753Gln Polymorphisms in Toll-Like Receptor 2 Gene are Associated with Tuberculosis Risk: A Meta-Analysis

BACKGROUND Numerous epidemiological studies have reported the association between polymorphisms of Toll-like receptor 2 (TLR2) and susceptibility to tuberculosis (TB). However, the results remain inconclusive. Therefore, we performed a quantitative meta-analysis to evaluate associations between the polymorphism of Arg753Gln of the TLR2 gene and susceptibility to TB. MATERIAL AND METHODS Three databases (PubMed, CNKI and Embase) were systematically searched for eligible studies. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) as our index were used to assess the relation between the TLR2 gene Arg753Gln polymorphism and risk of TB. Overall and subgroup analyses were conducted according to the available information. RESULTS With a detailed selection, 7 eligible studies with 1486 cases and 1322 controls were identified in our meta-analysis. There was a significant difference between TLR2 gene Arg753Gln polymorphism and the risk of TB (additive model: P<0.01, OR=2.89, 95% CI: 2.13-3.91; GA vs. GG: P<0.01, OR=2.92, 95% CI: 2.09-4.08). Interestingly, subgroup analysis based on ethnicity indicated that TB risk was significantly increased in Asians (additive model: P<0.01, OR=3.17, 95% CI: 2.31-4.35; GA vs. GG: P<0.01, OR=3.29, 95% CI: 2.32-4.68); by contrast, there was no association found in whites (additive model: P=0.40, OR=0.57, 95% CI: 0.15-2.13; GA vs. GG: P=0.40, OR=0.57, 95% CI: 0.15-2.13). CONCLUSIONS Our meta-analysis provides evidence that the TLR2 gene Arg753Gln polymorphism is a risk factor to TB, especially in Asian populations.