title: The -444A/C polymorphism in the LTC4S gene and the risk of asthma: a meta-analysis.
abstract: OBJECTIVE
  The -444A/C polymorphism in the leukotriene C4 synthase (LTC4S) gene has been implicated in susceptibility to asthma, but a large number of studies have reported inconclusive results. The aim of this study was to investigate the association between the -444A/C polymorphism in the LTC4S gene and asthma risk using meta-analysis.
  
  
  METHODS
  We searched Pubmed, Embase, CNKI and Wanfang databases. Statistical analysis was performed using the software Revman4.2 and STATA10.0.
  
  
  RESULTS
  A total of 3042 cases and 1902 controls in 13 case-control studies were included in the meta-analysis. The results indicated that the variant C allele carriers (CC + AC) did not have increased/decreased risk of asthma when compared with the homozygote AA (CC + AC vs. AA: OR = 1.13, 95% CI = 1.00-1.28, p = 0.06). In the subgroup analysis by age, ethnicity and aspirin sensitivity, significantly elevated risks were found only in Caucasians (OR = 1.21, 95% CI = 1.02-1.44, p = 0.03) and aspirin-tolerant populations (OR = 1.36, 95% CI = 1.12-1.65, p = 0.002) but not in other subgroups.
  
  
  CONCLUSIONS
  This meta-analysis suggested that the -444A/C polymorphism in the LTC4S gene would be a risk factor for asthma in Caucasians and aspirin-tolerant populations. Future studies are needed to validate our results.
authors.affiliation: Department of Respiratory Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan 610041, China.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Honglang
authors.initials: H
authors.lastname: Huang
authors.forename: Jichong
authors.initials: J
authors.lastname: Huang
authors.forename: Zhangpeng
authors.initials: Z
authors.lastname: Xiang
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.forename: Can
authors.initials: C
authors.lastname: Tian
authors.forename: Hong
authors.initials: H
authors.lastname: Fan
mesh_terms: D001249:Asthma / Q000453:epidemiology / Q000235:genetics*; D016022:Case-Control Studies; D020022:Genetic Predisposition to Disease; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D011110:Polymorphism, Genetic
chemical_list: D005982:Glutathione Transferase; C041116:leukotriene-C4 synthase