Vitamin D Receptor ApaI (rs7975232) Polymorphism Confers Decreased Risk of Pulmonary Tuberculosis in Overall and African Population, but not in Asians: Evidence from a Meta-analysis.

GOALS: The involvement of the VDR ApaI gene polymorphism in the development of pulmonary tuberculosis (PTB) has been reported by numerous published studies and yielded inconsistent results. The present meta-analysis evaluated the association of VDR ApaI polymorphism and risk of PTB occurrence.

PROCEDURES: PubMed (Medline), EMBASE and Google Scholar web-databases were searched and a meta-analysis was performed by calculating the pooled odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS: This meta-analysis included a total of 14 eligible studies comprising of 1958 confirmed PTB cases and 2938 controls. We observed decreased risk of PTB in allelic (a vs. A: p =0.003; OR=0.873, 95% CI=0.798 to 0.955), homozygous (aa vs. AA: p =0.006; OR=0.761, 95% CI=0.626 to 0.924), dominant (aa+Aa vs. AA: p =0.039; OR=0.874, 95% CI=0.769 to 0.993) and recessive (aa vs. AA+Aa: p =0.025; OR=0.819, 95% CI=0.688 to 0.975) genetic models. During subgroup analysis, allele (a vs. A: p =0.005; OR=0.846, 95% CI=0.753 to 0.951), homozygous (aa vs. AA: p =0.002; OR=0.662, 95% CI=0.513 to 0.854) and recessive genetic models (aa vs. AA+Aa: p=0.003; OR=0.709, 95% CI=0.566 to 0.889) demonstrated decreased PTB risk in African population. However, no significant association was observed in Asian population.

CONCLUSION: In conclusion, VDR ApaI polymorphism is significantly associated with decreased risk of PTB for in overall and African population, but not in Asians.