The effect of P2X7 receptor 1513 polymorphism on susceptibility to tuberculosis: A meta-analysis

•Nine studies involving 2195 cases and 2036 controls are included.•The associations between rs3751143 and both PTB and EPTB were separately analyzed.•Rs3751143 is associated with increased susceptibility to PTB and EPTB in Asians.•Population is one of the main sources of heterogeneity.

Studies of the association between the purinergic receptor P2X, ligand-gated ion channel 7 (P2X7 receptor) gene 1513A/C polymorphism and susceptibility to tuberculosis have yielded inconsistent results. We performed this meta-analysis to help clarify these inconsistencies. After systematically searching PUBMED, MEDLINE, EMBASE and ISI Web of knowledge, two of the authors independently extracted relevant data and a meta-analysis was performed by using STATA11.0 software. A total number of nine studies involving 2195 cases and 2036 controls were identified. The results indicated that P2X7 receptor gene 1513C allele (OR 1.389, 95% CI 1.161-1.660, p < 0.001) and CC genotype (1.582, 95% CI 1.129-2.217, p = 0. 012) were significantly associated with increased susceptibility to tuberculosis. Subgroup analysis indicated that this SNP greatly contributed to susceptibility to tuberculosis in Asians. The C allele of P2X7 receptor gene 1513A/C polymorphism was also associated with increased susceptibility to pulmonary tuberculosis in Asians (C vs. A: OR 1.420, 95% CI 1.163-1.733, p = 0.001; (CC + AC) vs. AA: OR 1.522, 95% CI 1.186-1.953, p = 0.001). Greater association between P2X7 receptor gene 1513A/C polymorphism and susceptibility to extra-pulmonary tuberculosis with bigger ORs were found (C vs. A, OR 2.035, 95% CI 1.236-3.352, p = 0.005; CC vs. AA, OR 3.788, 95% CI 1.434-10.009, p = 0.007; AC vs. AA, OR 2.148, 95% CI 1.252-3.684, p = 0.005; (CC + AC) vs. AA, OR 2.386, 95% CI 1.302-4.374, p = 0.005; CC vs. (AC + AA), OR 2.692, 95% CI 1.242-5.836, p = 0. 012). This meta-analysis indicates that the C allele of P2X7 receptor gene 1513A/C polymorphism is a risk factor for pulmonary tuberculosis in Asians, while not in Africans or Latinos and a risk for extra-pulmonary tuberculosis. Further well-designed, large scale studies are required to confirm this conclusion.