title: Estrogen metabolizing polymorphisms and breast cancer risk among older white women.
abstract: OBJECTIVE
  To investigate breast cancer risk according to metabolizing genes polymorphisms in older women.
  
  
  METHODS
  A subset (43.8%) of 4248 older, white women from the Study of Osteoporotic Fractures (SOF) were genotyped for the catechol-O-methyltransferase (COMT) Val108Met polymorphism and the CYP1A1*2C locus. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between genotypes and breast cancer while controlling for potential confounders.
  
  
  RESULTS
  During a mean follow up of 12.4 years, 252 women (5.9%) developed breast cancer. The HR (95% CI) for breast cancer was 1.24 (0.87-1.75) for COMT(Val/Met) and 1.35 (0.93-1.97) for COMT(Met/Met). No interactions with lifestyle and reproductive factors were found. The HR associated with the CYP1A1*2C Val allele was 0.80 (0.46, 1.39) with little evidence for interactions with lifestyle or reproductive factors.
  
  
  CONCLUSIONS
  Among older white women, neither the COMT Val108/158Met polymorphism nor the CYP1A*2C Val allele plays a major role in breast cancer risk either alone or in combination with lifestyle and reproductive factors.
authors.affiliation: Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, PA, USA. modugno+@pitt.edu
authors.forename: Francesmary
authors.initials: F
authors.lastname: Modugno
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Zmuda
authors.forename: Douglas
authors.initials: D
authors.lastname: Potter
authors.forename: Chao
authors.initials: C
authors.lastname: Cai
authors.forename: Elad
authors.initials: E
authors.lastname: Ziv
authors.forename: Steven R
authors.initials: SR
authors.lastname: Cummings
authors.forename: Katie L
authors.initials: KL
authors.lastname: Stone
authors.forename: Phillip A
authors.initials: PA
authors.lastname: Morin
authors.forename: Deborah
authors.initials: D
authors.lastname: Greene
authors.forename: Jane A
authors.initials: JA
authors.lastname: Cauley
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000208:ethnology / Q000235:genetics*; D016022:Case-Control Studies; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D004967:Estrogens / Q000378:metabolism; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000208:ethnology / Q000235:genetics*; D006801:Humans; D008019:Life Style; D020641:Polymorphism, Single Nucleotide; D016016:Proportional Hazards Models; D011446:Prospective Studies; D017584:Reproductive History; D012306:Risk; D014481:United States / Q000453:epidemiology; D044465:White People / Q000235:genetics*
chemical_list: D004967:Estrogens; D019363:Cytochrome P-450 CYP1A1; D002394:Catechol O-Methyltransferase