title: GSTM1 and GSTT1 polymorphisms and colorectal cancer risk in Chinese population: a meta-analysis.
abstract: OBJECTIVE
  Studies investigating the associations between GSTM1 and GSTT1 polymorphisms and colorectal cancer (CRC) risk in Chinese population have reported controversial results. Thus, a meta-analysis was performed.
  
  
  METHODS
  Four hundred and seven relevant records were identified through a literature search up to September 7, 2011, and 19 studies were finally included, involving a total of 3,130 CRC cases and 6,423 controls. Subgroup analyses were performed by language and study design. Statistical analysis was performed with the software programs Review Manager (version 5.1.2) and STATA (version 11.0).
  
  
  RESULTS
  For the GSTM1 polymorphism, the null genotype of GSTM1 was not associated with CRC risk in Chinese population (OR = 1.12, 95% CI = 0.97-1.28). Similar associations were found for GSTT1 polymorphism (OR = 1.10, 95% CI = 0.94-1.29) and the dual null genotype of GSTM1/GSTT1 (OR = 1.26, 95% CI = 0.93-1.71). For subgroup analyses, studies published in English and population-based studies further identified these associations for the three aspects above in Chinese population.
  
  
  CONCLUSIONS
  This meta-analysis suggests that the null genotypes of GSTM1 and GSTT1 and the dual null genotype of GSTM1/GSTT1 were all not risk factors in CRC in Chinese population.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Hebei Medical University, No. 361 Zhongshan East Road, Shijiazhuang, 050017 Hebei Province, China. danw126@126.com
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Li-Mei
authors.initials: LM
authors.lastname: Zhang
authors.forename: Jun-Xia
authors.initials: JX
authors.lastname: Zhai
authors.forename: Dian-Wu
authors.initials: DW
authors.lastname: Liu
mesh_terms: D044466:Asian People / Q000235:genetics*; D002681:China; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D017594:Publication Bias; D012307:Risk Factors
chemical_list: D005982:Glutathione Transferase; C413545:glutathione S-transferase T1