title: CYP1A2 164 A-->C polymorphism, cigarette smoking, consumption of well-done red meat and risk of developing colorectal adenomas and carcinomas.
abstract: BACKGROUND
  Genetic polymorphisms in metabolizing enzymes may modify the association of environmental exposure on colorectal cancer (CRC) and adenoma risk.
  
  
  METHODS
  One hundred and ninety-eight CRC cases, 422 adenomas (206 low-risk and 216 high-risk adenomas) and 222 controls were genotyped for the CYP1A2 164 A-->C polymorphism and questionnaires were used to assess environmental exposure.
  
  
  RESULTS
  The smoking parameter "current smoking" was significantly associated with CRC risk, and all the smoking parameters related to current smoking, having ever smoked or high numbers of cigarette years were significantly associated with risk of adenomas. No association was detected between red meat consumption or how well red meat was cooked and colorectal carcinogenesis. When stratifying the case groups based on CYP1A2 genotype, all the smoking parameters yielded stronger risk association in carriers of the C allele.
  
  
  CONCLUSIONS
  These findings may indicate that the association between cigarette smoking and colorectal carcinogenesis can be modified by the CYP1A2 genotype.
authors.affiliation: Telemark University College, Faculty of Arts and Sciences, Bø i Telemark, Norway.
authors.forename: Mona
authors.initials: M
authors.lastname: Saebø
authors.forename: Camilla F
authors.initials: CF
authors.lastname: Skjelbred
authors.forename: Karin
authors.initials: K
authors.lastname: Brekke Li
authors.forename: Inger Marie
authors.initials: IM
authors.lastname: Bowitz Lothe
authors.forename: Per Chr
authors.initials: PC
authors.lastname: Hagen
authors.forename: Egil
authors.initials: E
authors.lastname: Johnsen
authors.forename: Kjell M
authors.initials: KM
authors.lastname: Tveit
authors.forename: Elin H
authors.initials: EH
authors.lastname: Kure