title: Genetic polymorphisms in biotransformation enzymes in Crohn's disease: association with microsomal epoxide hydrolase.
abstract: BACKGROUND
  Mucosal biotransformation enzymes can modify toxic compounds in the gut. As chemical or oxidative stress may be involved in the aetiology of Crohn's disease, genes encoding for enzymes involved in the prevention of such stress may be candidates for genetic susceptibility to Crohn's disease.
  
  
  OBJECTIVE
  To assess the association of Crohn's disease with genetic polymorphisms in cytochrome P450 1A1, glutathione S-transferases mu-1, pi-1, and theta-1, and epoxide hydrolase.
  
  
  METHODS
  chi(2) square analysis was used to compare frequencies of polymorphisms between 151 patients with Crohn's disease and 149 healthy controls.
  
  
  RESULTS
  In patients, a genetic polymorphism in exon 3 of the microsomal epoxide hydrolase gene was distributed significantly different compared with controls (chi(2)=23.7; p<0.0001). All other polymorphisms tested were equally distributed between patients and controls.
  
  
  CONCLUSIONS
  Microsomal epoxide hydrolase may play a role in the pathophysiology of Crohn's disease. Furthermore, the epoxide hydrolase gene is located on chromosome 1q, close to a region previously linked to Crohn's disease.
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Centre Nijmegen, the Netherlands. d.dejong@gastro.azn.nl
authors.forename: D J
authors.initials: DJ
authors.lastname: de Jong
authors.forename: E M J
authors.initials: EM
authors.lastname: van der Logt
authors.forename: A
authors.initials: A
authors.lastname: van Schaik
authors.forename: H M J
authors.initials: HM
authors.lastname: Roelofs
authors.forename: W H M
authors.initials: WH
authors.lastname: Peters
authors.forename: T H J
authors.initials: TH
authors.lastname: Naber
mesh_terms: D000328:Adult; D001711:Biotransformation / Q000235:genetics; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D003424:Crohn Disease / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics; D004851:Epoxide Hydrolases / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005982:Glutathione Transferase / Q000235:genetics; D006801:Humans; D008297:Male; D008861:Microsomes / Q000201:enzymology; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length
chemical_list: D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase; D004851:Epoxide Hydrolases