title: The cytochrome P4501A1 gene polymorphisms and endometriosis: a meta-analysis.
abstract: OBJECTIVE
  Cytochrome P450 1A1 (CYP1A1) polymorphisms were implicated in endometriosis risk, but individual published studies showed inconclusive results. Thus, a meta-analysis was performed to clarify the effect of CYP1A1 polymorphisms on endometriosis risk.
  
  
  METHODS
  PubMed, Embase, and CNKI databases were searched to identify the eligible studies focusing on the associations between CYP1A1 MspI and Ile462Val polymorphisms and susceptibility to endometriosis. Summary odds ratios (ORs) and 95 % confidence intervals (95 % CIs) for CYP1A1 polymorphisms and endometriosis were calculated.
  
  
  RESULTS
  Pooled analysis of 12 studies involved a total of 1555 cases and 2868 controls showed that in all genetic models, no significant association between CYP1A1 MspI polymorphism and endometriosis risk was observed in the overall, Asians and Caucasians population, respectively. Interestingly, increased endometriosis risk was associated with carrying the C allele of CYP1A1 combined with GSTM1 null genotypes. For CYP1A1 Ile462Val polymorphism, eight studies were available (878 cases and 1991 controls). In the overall analysis, CYP1A1 Ile462Val polymorphism had a statistically significant association with increased endometriosis risk in allele contrast and all genetic models except the model of Val/Ile vs. Ile/Ile. In the subgroup analysis by ethnicity, significant elevated endometriosis risk was associated with CYP1A1 Ile462Val polymorphism in Asians but not in Caucasians under all genetic models. No publication bias was found in the present studies.
  
  
  CONCLUSIONS
  This meta-analysis suggested that CYP1A1 Ile462Val polymorphism was associated with an increased risk of endometriosis, particularly in Asians. CYP1A1 MspI polymorphism may not be associated with endometriosis risk, but GSTM1 and CYP1A1 MspI polymorphism may have a joint effect on endometriosis risk.
authors.affiliation: Center of Reproductive Medicine, The West China Second University Hospital, Sichuan University, Sichuan, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Fan
authors.affiliation: Center of Reproductive Medicine, The West China Second University Hospital, Sichuan University, Sichuan, People's Republic of China.
authors.forename: Zhongying
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Center of Reproductive Medicine, The West China Second University Hospital, Sichuan University, Sichuan, People's Republic of China.
authors.forename: Zhun
authors.initials: Z
authors.lastname: Xiao
authors.affiliation: Center of Reproductive Medicine, The West China Second University Hospital, Sichuan University, Sichuan, People's Republic of China.
authors.forename: Shangwei
authors.initials: S
authors.lastname: Li
authors.affiliation: Center of Reproductive Medicine, The West China Second University Hospital, Sichuan University, Sichuan, People's Republic of China. qianhong_ma@163.com.
authors.forename: Qianhong
authors.identifier: http://orcid.org/0000-0002-7631-4546
authors.initials: Q
authors.lastname: Ma
mesh_terms: D044466:Asian People; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D004715:Endometriosis / Q000235:genetics* / Q000473:pathology; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D044465:White People
chemical_list: D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase; C569463:CYP1A1 protein, human
keywords: Cytochrome P450 1A1; Endometriosis; Meta-analysis; Polymorphism