title: Intron 3 sixteen base pairs duplication polymorphism of p53 contributes to breast cancer susceptibility: evidence from meta-analysis.
abstract: BACKGROUND
  P53 is a tumor suppressor gene and plays important role in the etiology of breast cancer. Intron 3 sixteen-bp duplication polymorphism of p53 has been reported to be associated with breast cancer risk. However, the reported results remain conflicting rather than conclusive.
  
  
  METHODS
  A meta-analysis including 19 case-control studies was performed to address this issue. Odds ratios (ORs) with 95% confidence intervals (CIs) were adopted to evaluate the association.
  
  
  RESULTS
  The overall results suggested that the variant genotypes were associated with a significantly increased breast cancer risk (Del/Ins vs Del/Del: OR = 1.18, 95% CI: 1.00-1.40; Ins/Ins vs Del/Del: OR = 1.42, 95% CI = 1.09-1.84; Ins/Ins+Del/Ins vs Del/Del: OR = 1.21, 95% CI = 1.03-1.41). When stratifying by sample size of studies, a significantly elevated risk was also observed among large sample studies (>500 subjects) but not among small sample studies (≤500 subjects).
  
  
  CONCLUSIONS
  These results suggested that the 16-bp duplication polymorphism of p53 may contribute to susceptibility to breast cancer. Additional well-designed large studies were required to validate this association in different populations.
authors.affiliation: Department of Environmental Genomics, Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Cancer Center, Nanjing Medical University, Nanjing, China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Wu
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Zhang
authors.forename: Haiyan
authors.initials: H
authors.lastname: Chu
authors.forename: Ming
authors.initials: M
authors.lastname: Xu
authors.forename: Yao
authors.initials: Y
authors.lastname: Xue
authors.forename: Haixia
authors.initials: H
authors.lastname: Zhu
authors.forename: Zhengdong
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D020029:Base Pairing / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics*; D005260:Female; D020440:Gene Duplication; D020022:Genetic Predisposition to Disease; D006801:Humans; D007438:Introns / Q000235:genetics*; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D017594:Publication Bias; D012307:Risk Factors; D016159:Tumor Suppressor Protein p53 / Q000235:genetics
chemical_list: C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53