title: Genetic variants associated with breast-cancer risk: comprehensive research synopsis, meta-analysis, and epidemiological evidence.
abstract: BACKGROUND
  More than 1000 reports have been published in the past two decades on associations between variants in candidate genes and risk of breast cancer. Results have been generally inconsistent. We did a literature search and meta-analyses to provide a synopsis of the current understanding of the genetic architecture of breast-cancer risk.
  
  
  METHODS
  A systematic literature search for candidate-gene association studies of breast-cancer risk was done in two stages, using PubMed on or before Feb 28, 2010. A total of 24,500 publications were identified, of which 1059 were deemed eligible for inclusion. Meta-analyses were done for 279 genetic variants in 128 candidate genes or chromosomal loci that had at least three data sources. Variants with significant associations by meta-analysis were assessed using the Venice criteria and scored as having strong, moderate, or weak cumulative evidence for an association with breast-cancer risk.
  
  
  RESULTS
  51 variants in 40 genes showed significant associations with breast-cancer risk. Cumulative epidemiological evidence of an association was graded as strong for ten variants in six genes (ATM, CASP8, CHEK2, CTLA4, NBN, and TP53), moderate for four variants in four genes (ATM, CYP19A1, TERT, and XRCC3), and weak for 37 variants. Additionally, in meta-analyses that included a minimum of 10,000 cases and 10,000 controls, convincing evidence of no association with breast-cancer risk was identified for 45 variants in 37 genes.
  
  
  CONCLUSIONS
  Whereas most genetic variants assessed in previous candidate-gene studies showed no association with breast-cancer risk in meta-analyses, 14 variants in nine genes had moderate to strong evidence for an association. Further evaluation of these variants is warranted.
  
  
  BACKGROUND
  US National Cancer Institute.
authors.affiliation: Division of Epidemiology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA.
authors.forename: Ben
authors.initials: B
authors.lastname: Zhang
authors.forename: Alicia
authors.initials: A
authors.lastname: Beeghly-Fadiel
authors.forename: Jirong
authors.initials: J
authors.lastname: Long
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
mesh_terms: D015703:Antigens, CD / Q000235:genetics; D001141:Aromatase / Q000235:genetics; D064007:Ataxia Telangiectasia Mutated Proteins; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000235:genetics*; D060908:CTLA-4 Antigen; D053181:Caspase 8 / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics; D064447:Checkpoint Kinase 2; D004268:DNA-Binding Proteins / Q000235:genetics; D019317:Evidence-Based Medicine; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D018570:Risk Assessment; D012307:Risk Factors; D019098:Telomerase / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000235:genetics
chemical_list: D015703:Antigens, CD; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C112156:NBN protein, human; D009687:Nuclear Proteins; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; C110901:X-ray repair cross complementing protein 3; D001141:Aromatase; D064447:Checkpoint Kinase 2; C576324:ATM protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; C578634:CHEK2 protein, human; D017346:Protein Serine-Threonine Kinases; C509186:TERT protein, human; D019098:Telomerase; C505530:CASP8 protein, human; D053181:Caspase 8