title: Current evidence on the relationship between two polymorphisms in the NBS1 gene and breast cancer risk: a meta-analysis.
abstract: BACKGROUND
  Published studies on the association between Nijmegen breakage syndrome 1(NBS1) gene polymorphisms and breast cancer risk have been inconclusive, and a meta-analysis was therefore performed for clarification.
  
  
  METHODS
  Eligible articles were identified by a search of MEDLINE and EMBASE bibliographic databases for the period up to March 2012. The presence of between-study heterogeneity was investigated using the chi-square-based Cochran's Q statistic test. When there was statistical heterogeneity, the random effects model was chosen; otherwise, fixed effects estimates were reported as an alternative approach.
  
  
  RESULTS
  A total of 11 eligible articles (14 case-control studies) were identified, nine case-control studies were for the 657del5 mutation (7,534 breast cancer cases, 14,034 controls) and five case-control studies were for the I171V mutation (3,273 breast cancer cases, 4,004 controls). Our analysis results indicated that the 657del5 mutation was associated with breast cancer risk (carriers vs. non- carriers: pooled OR=2.63, 95% CI: 1.76-3.93), whereas the I171V mutation was not (carriers vs. non-carriers: pooled OR=1.52, 95% CI: 0.70-3.28).
  
  
  CONCLUSIONS
  The present meta-analysis suggests that the 657del5 gene mutation in the NBS1 gene plays a role in breast cancer risk, while the I171V mutation does not exert a significant influence.
authors: Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, Anhui, China.
authors: Zhi-Hua
authors: ZH
authors: Zhang
authors: Lin-Sheng
authors: LS
authors: Yang
authors: Fen
authors: F
authors: Huang
authors: Jia-Hu
authors: JH
authors: Hao
authors: Pu-Yu
authors: PY
authors: Su
authors: Ye-Huan
authors: YH
authors: Sun
mesh_terms: D001943:Breast Neoplasms / Q000209:etiology*; D016022:Case-Control Studies; D018797:Cell Cycle Proteins / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D009154:Mutation / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012307:Risk Factors; D017384:Sequence Deletion / Q000235:genetics*
chemical_list: D018797:Cell Cycle Proteins; C112156:NBN protein, human; D009687:Nuclear Proteins