title: Association of vitamin D receptor gene polymorphisms in Iranian patients with inflammatory bowel disease.
abstract: OBJECTIVE
  The vitamin D receptor (VDR) gene maps to a region on chromosome 12 shown to be linked to inflammatory bowel disease (IBD). Many studies have recognized the relation of VDR gene polymorphisms with inflammatory and autoimmune disorders. Determining the frequency of these polymorphisms and their possible relation with IBD can improve understandings about the genetic background of these diseases. The objective of this study was to assess the association of VDR gene polymorphisms (Apa I, Taq I, Bsm I, Fok I) with IBD in Iran.
  
  
  METHODS
  In this case control designed study 150 patients with ulcerative colitis, 80 patients with Crohn's disease and 150 Age and Sex matched healthy controls from Iranian origin were enrolled. These patients were referred to a tertiary center during a two-year period (2004-2006). Assessment of VDR gene polymorphisms was performed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The genotype-phenotype association for these polymorphisms was analyzed.
  
  
  RESULTS
  Only the frequency of the Fok I polymorphism was significantly higher in ulcerative colitis and Crohn's groups. The frequency of the polymorphic allele f was higher in ulcerative colitis and Crohn's patients comparing with controls (P = 0.011 and P < 0.001, respectively). The f/f genotype was also significantly more frequent (P < 0.001), while the F/F genotype was less presented in Crohn's patients compared to controls (P < 0.001). No genotype-phenotype association was observed with any mutations.
  
  
  CONCLUSIONS
  This study suggests a probable association of the Fok I polymorphism in VDR receptor gene and Crohn's susceptibility in Iranian population.
authors.affiliation: Research Center for Gastroenterology and Liver Diseases, Shahid Beheshti University, MC, Tehran, Iran.
authors.forename: Nosratollah
authors.initials: N
authors.lastname: Naderi
authors.forename: Alma
authors.initials: A
authors.lastname: Farnood
authors.forename: Manijeh
authors.initials: M
authors.lastname: Habibi
authors.forename: Faramarz
authors.initials: F
authors.lastname: Derakhshan
authors.forename: Hedieh
authors.initials: H
authors.lastname: Balaii
authors.forename: Zahra
authors.initials: Z
authors.lastname: Motahari
authors.forename: Mohammad R
authors.initials: MR
authors.lastname: Agah
authors.forename: Farzad
authors.initials: F
authors.lastname: Firouzi
authors.forename: Mahta G
authors.initials: MG
authors.lastname: Rad
authors.forename: Rahim
authors.initials: R
authors.lastname: Aghazadeh
authors.forename: Homayoun
authors.initials: H
authors.lastname: Zojaji
authors.forename: Mohammad R
authors.initials: MR
authors.lastname: Zali