title: Lack of association between GSTM1 and GSTT1 polymorphisms and brain tumour risk.
abstract: OBJECTIVE
  Glutathione S-transferases (GSTs) are important enzymes that are involved in detoxification of environmental carcinogens. Molecular epidemiological studies have been conducted to investigate the association between GSTM1 and GSTT1 homozygous deletion polymorphisms and brain tumours but results have been conflicting. The aim of this study was to clarify this problem using a meta-analysis.
  
  
  METHODS
  A total of 9 records were identified by searching the PubMed and Embase databases. Fixed- and random-effects models were performed to estimate the pooled odds ratios.
  
  
  RESULTS
  No significant association was found between the GSTM1 and GSTT1 homozygous deletion polymorphisms and risk of brain tumours, including glioma and meningioma. Similar negative results were also observed in both population-based and hospital-based studies.
  
  
  CONCLUSIONS
  These findings indicate that the GSTM1 and GSTT1 polymorphisms may not be related to the development of brain tumours.
authors.affiliation: Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, China.
authors.forename: Xiu-Tian
authors.initials: XT
authors.lastname: Sima
authors.forename: Wei-Ying
authors.initials: WY
authors.lastname: Zhong
authors.forename: Jian-Gang
authors.initials: JG
authors.lastname: Liu
authors.forename: Chao
authors.initials: C
authors.lastname: You
mesh_terms: D001932:Brain Neoplasms / Q000453:epidemiology / Q000235:genetics*; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D020022:Genetic Predisposition to Disease; D005910:Glioma / Q000453:epidemiology / Q000235:genetics*; D005982:Glutathione Transferase / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D008577:Meningeal Neoplasms / Q000453:epidemiology / Q000235:genetics*; D015201:Meta-Analysis as Topic; D011110:Polymorphism, Genetic / Q000235:genetics*; D011379:Prognosis; D012307:Risk Factors
chemical_list: D005982:Glutathione Transferase; C413545:glutathione S-transferase T1