title: Polymorphisms in the cytochrome P450 genes CYP1A2, CYP1B1, CYP3A4, CYP3A5, CYP11A1, CYP17A1, CYP19A1 and colorectal cancer risk.
abstract: BACKGROUND
  Cytochrome P450 (CYP) enzymes have the potential to affect colorectal cancer (CRC) risk by determining the genotoxic impact of exogenous carcinogens and levels of sex hormones.
  
  
  METHODS
  To investigate if common variants of CYP1A2, CYP1B1, CYP3A4, CYP3A5, CYP11A1, CYP17A1 and CYP19A1 influence CRC risk we genotyped 2,575 CRC cases and 2,707 controls for 20 single nucleotide polymorphisms (SNPs) that have not previously been shown to have functional consequence within these genes.
  
  
  RESULTS
  There was a suggestion of increased risk, albeit insignificant after correction for multiple testing, of CRC for individuals homozygous for CYP1B1 rs162558 and heterozygous for CYP1A2 rs2069522 (odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.03-1.80 and OR = 1.34, 95% CI: 1.00-1.79 respectively).
  
  
  CONCLUSIONS
  This study provides some support for polymorphic variation in CYP1A2 and CYP1B1 playing a role in CRC susceptibility.
authors.affiliation: Section of Cancer Genetics, Institute of Cancer Research, Surrey, UK. lara.bethke@icr.ac.uk <lara.bethke@icr.ac.uk>
authors.forename: Lara
authors.initials: L
authors.lastname: Bethke
authors.forename: Emily
authors.initials: E
authors.lastname: Webb
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Sellick
authors.forename: Matthew
authors.initials: M
authors.lastname: Rudd
authors.forename: Stephen
authors.initials: S
authors.lastname: Penegar
authors.forename: Laura
authors.initials: L
authors.lastname: Withey
authors.forename: Mobshra
authors.initials: M
authors.lastname: Qureshi
authors.forename: Richard
authors.initials: R
authors.lastname: Houlston
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D016001:Confidence Intervals; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D020022:Genetic Predisposition to Disease / Q000453:epidemiology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D011379:Prognosis; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D016019:Survival Analysis
chemical_list: D003577:Cytochrome P-450 Enzyme System