title: Glutathione S-transferase M1 polymorphism and coronary heart disease susceptibility: a meta-analysis involving 47,596 subjects.
abstract: BACKGROUND
  Many studies have investigated the association between glutathione S-transferase M1 (GSTM1) null genotype and the risk of coronary heart disease (CHD). However, the effect of the GSTM1 null genotype on CHD is still unclear because of apparent inconsistencies among those studies. A meta-analysis was performed to characterise the relationship more accurately.
  
  
  METHODS
  Pubmed, Embase, and Web of Science were searched. We estimated the summary odds ratio (OR) with a 95% confidence interval (95% CI) to assess the association.
  
  
  RESULTS
  Up to 26 case-control studies with 13,929 CHD cases and 33,667 control cases were included into this meta-analysis. Meta-analysis of the 26 studies showed that GSTM1 null genotype was associated with the risk of CHD (random effects OR=1.35, 95% CI 1.00 to 1.83). After adjustment for heterogeneity, meta-analysis showed that GSTM1 null genotype was not associated with increased risk of CHD in the total population (fixed effects OR=1.01, 95% CI 0.95 to 1.07). In the subgroup analysis by ethnicity, increased risks were not found for either Caucasians (OR=1.36, 95% CI=0.96-1.92) or Asians (OR=1.28, 95% CI=0.91-1.80). When stratified by smoking status, in the subgroup of smokers, GSTM1 null genotype was significantly associated with increased CHD risk (random effects OR=1.64, 95% CI 1.02 to 2.64). No evidence of publication bias was observed.
  
  
  CONCLUSIONS
  In conclusion, this meta-analysis suggested that there is overall lack of association between GSTM1 genotypes and CHD risk, however, GSTM1 null genotype when combining with smoking history may contribute to CHD susceptibility.
authors: Department of Cardiology, the Fourth Affiliated Hospital of China Medical University, Shenyang 110032, China.
authors: Donghui
authors: D
authors: Zhou
authors: Department of Cardiology, the Fourth Affiliated Hospital of China Medical University, Shenyang 110032, China.
authors: Weina
authors: W
authors: Hu
authors: Department of Cardiology, the Fourth Affiliated Hospital of China Medical University, Shenyang 110032, China.
authors: Qi
authors: Q
authors: Wang
authors: Department of Cardiology, the Fourth Affiliated Hospital of China Medical University, Shenyang 110032, China. Electronic address: yuanzhe_jin@126.com.
authors: Yuanzhe
authors: Y
authors: Jin
mesh_terms: D016022:Case-Control Studies; D003327:Coronary Disease / Q000201:enzymology / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic
chemical_list: D005982:Glutathione Transferase
keywords: Coronary heart disease; GSTM1; Meta-analysis; Polymorphism; Smoking