title: Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and susceptibility for cervical lesions: a meta-analysis.
abstract: BACKGROUND
  The association between the methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and the susceptibility to cervical lesions was unclear. This study was designed to investigate their precise association using a large-scale meta-analysis.
  
  
  METHODS
  The previous 16 studies were identified by searching PubMed, Embase and CBM databases. The crude odds ratios and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the MTHFR C677T/A1298C polymorphisms and the susceptibility to the cervical lesions. The subgroup analyses were made on the following: pathological history, geographic region, ethnicity, source of controls and source of DNA for genotyping.
  
  
  RESULTS
  Neither of the polymorphisms had a significant association with the susceptibility to the cervical lesions in all genetic models. Similar results were found in the subgroup analyses. No association was found between the MTHFR C677T polymorphism and the cervical lesions in the Asia or the America populations though a significant inverse association was found in the Europe population (additive model: P = 0.006, OR = 0.83, 95% CI = 0.72-0.95; CT vs. CC: P = 0.05, OR = 0.83, 95% CI = 0.69-1.00; TT vs. CC: P = 0.05, OR = 0.73, 95% CI = 0.53-1.00). Interestingly, women with the MTHFR A1298C polymorphisms had a marginally increased susceptibility to invasive cancer (ICC) when compared with no carriers but no statistically significant difference in the dominant model (P = 0.06, OR = 1.21, 95% CI = 0.99-1.49) and AC vs. AA (P = 0.09, OR = 1.21, 95% CI = 0.97-1.51).
  
  
  CONCLUSIONS
  The MTHFR C677T and A1298C polymorphisms may not increase the susceptibility to cervical lesions. However, the meta-analysis reveals a negative association between the MTHFR C677T polymorphisms and the cervical lesions, especially in the European populations. The marginal association between the MTHFR A1298C polymorphisms and the susceptibility to cervical cancer requires a further study.
authors.affiliation: Department of Gynecology and Obstetrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Shuyu
authors.initials: S
authors.lastname: Long
authors.forename: Xingliang
authors.initials: X
authors.lastname: Yang
authors.forename: Xiaojiao
authors.initials: X
authors.lastname: Liu
authors.forename: Pei
authors.initials: P
authors.lastname: Yang
mesh_terms: D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D017594:Publication Bias; D012307:Risk Factors; D002583:Uterine Cervical Neoplasms / Q000201:enzymology* / Q000235:genetics*
chemical_list: C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2)