title: The +252A/G polymorphism in the lymphotoxin-α gene increases the risk of asthma: a meta-analysis.
abstract: OBJECTIVE
  A number of studies have shown that the +252A/G polymorphism (rs909253) in the lymphotoxin-α (LT-α) gene is implicated in susceptibility to asthma. However, the findings have been inconclusive. The aim of this study was to investigate the association between the +252A/G polymorphism in the LT-α gene and the risk of asthma by performing a meta-analysis.
  
  
  METHODS
  The Pubmed and Embase databases were searched for all studies relating to this polymorphism and the risk of asthma. Statistical analyses were performed using the Revman4.2 and STATA 10.0 software.
  
  
  RESULTS
  Thirteen case-control studies that included a total of 2220 cases and 6428 controls were included in the meta-analysis. There was no significant association between this polymorphism and the risk of asthma in the all-combined analysis (odds ratio (OR) 1.14, 95% confidence interval (CI): 0.89-1.45 for GG+GA vs AA). In a subgroup analysis by ethnicity, no significant association with asthma risk was identified in Asians (OR 1.31, 95% CI: 0.97-1.77) or Europeans (OR 1.08, 95% CI: 0.77-1.53). In a subgroup analysis by age, a significantly increased risk was identified among adults (OR 1.25, 95% CI: 1.03-1.50) but not children (OR 1.04, 95% CI: 0.28-3.89). In a subgroup analysis by atopic status, a significantly elevated risk was identified among atopic (OR 1.55, 95% CI: 1.28-1.87) but not non-atopic individuals (OR 0.94, 95% CI: 0.53-1.68).
  
  
  CONCLUSIONS
  This meta-analysis suggested that the +252A/G polymorphism in the LT-α gene is a risk factor for asthma in adults and atopic populations.
authors.affiliation: Department of Respiratory Medicine, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Fu
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: He
authors.forename: Can
authors.initials: C
authors.lastname: Tian
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.forename: Hong
authors.initials: H
authors.lastname: Fan
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics; D001249:Asthma / Q000208:ethnology / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008233:Lymphotoxin-alpha / Q000235:genetics*; D008297:Male; D011110:Polymorphism, Genetic; D012306:Risk; D044465:White People / Q000235:genetics; D055815:Young Adult
chemical_list: D008233:Lymphotoxin-alpha