title: Association of vitamin D receptor BsmI gene polymorphism with risk of tuberculosis: a meta-analysis of 15 studies.
abstract: BACKGROUND
  Genetic variations in vitamin D receptor (VDR) may contribute to tuberculosis (TB) risk. Many studies have investigated the association between VDR BsmI gene polymorphism and TB risk, but yielded inconclusive results.
  
  
  RESULTS
  We performed a comprehensive meta-analysis of 15 publications with a total of 2309 cases and 3568 controls. We assessed the strength of the association between VDR BsmI gene polymorphism and TB risk and performed sub-group analyses by ethnicity, sample size and Hardy-Weinberg equilibrium (HWE). We found a statistically significant correlation between VDR BsmI gene polymorphism and decreased TB risk in four comparison models: allele model (b vs. B: OR = 0.78, 95% CI = 0.67, 0.89; Pheterogeneity = 0.004), homozygote model (bb vs. BB: OR = 0.61, 95% CI = 0.43, 0.87; Pheterogeneity = 0.001), recessive model (bb vs. Bb+BB: OR = 0.70, 95% CI = 0.56, 0.88; Pheterogeneity = 0.005) and dominant model (bb+Bb vs. BB: OR = 0.77, 95% CI = 0.61, 0.97; Pheterogeneity = 0.010), especially in studies based on Asian population. Sub-group analyses also revealed that there was a statistically decreased TB risk in "small" studies (<500 participants) and studies with PHWE>0.5. Meta-regression and stratification analysis both showed that the ethnicity and sample size contributed to heterogeneity.
  
  
  CONCLUSIONS
  This meta-analysis suggests that VDR BsmI gene polymorphism is associated with a significant decreased TB risk, especially in Asian population.
authors.affiliation: Department of Pharmacy, Changzhou Third People's Hospital, Changzhou, China.
authors.forename: Yu-Jiao
authors.initials: YJ
authors.lastname: Wu
authors.forename: Xin
authors.initials: X
authors.lastname: Yang
authors.forename: Xiao-Xiao
authors.initials: XX
authors.lastname: Wang
authors.forename: Man-Tang
authors.initials: MT
authors.lastname: Qiu
authors.forename: Yi-Zhong
authors.initials: YZ
authors.lastname: You
authors.forename: Zhi-Xin
authors.initials: ZX
authors.lastname: Zhang
authors.forename: Shan-Mei
authors.initials: SM
authors.lastname: Zhu
authors.forename: Lin
authors.initials: L
authors.lastname: Xu
authors.forename: Feng-Lei
authors.initials: FL
authors.lastname: Tang
mesh_terms: D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D011110:Polymorphism, Genetic; D018167:Receptors, Calcitriol / Q000235:genetics*; D014376:Tuberculosis / Q000235:genetics*
chemical_list: D018167:Receptors, Calcitriol