title: Associations of vitamin D receptor gene polymorphisms FokI and BsmI with susceptibility to rheumatoid arthritis and Behçet's disease in Tunisians.
abstract: OBJECTIVE
  Reports of immunomodulating effects of vitamin D suggest a need for examining allele and genotype frequencies of the vitamin D nuclear receptor gene (VDR) in patients with autoimmune diseases. T-helper-1 (Th1) counts in peripheral blood are increased in both rheumatoid arthritis (RA) and Behçet's disease (BD). We studied VDR polymorphisms in patients with these two diseases in Tunisia.
  
  
  METHODS
  In 108 patients with RA, 131 patients with BD, and 152 controls, we studied FokI and BsmI VDR polymorphisms, using the restriction fragment length polymorphism technique.
  
  
  RESULTS
  The FokI polymorphism alleles and genotype were significantly more common in the RA group than in the controls (P=0.001 and P=0.005, respectively). The FokI F allele and F/F genotype were significantly associated with BD (P=0.0003 and P=0.002, respectively). Furthermore, in the group with BD, the FokI polymorphism was significantly associated with the presence of vascular manifestations (P=0.006). In patients with RA, the FokI polymorphism was significantly associated with female gender (P=0.003). No significant associations were found between the Bsm1 polymorphism and RA or BD.
  
  
  CONCLUSIONS
  The VDR F allele is associated with RA and BD in Tunisians.
authors.affiliation: School of Medicine, Tunis El Manar University, Homeostasis and Cell Dysfunction Unit Research 99/UR/08-40, Tunis, Tunisia. emna2fakh@yahoo.fr
authors.forename: Emna Fakhfakh
authors.initials: EF
authors.lastname: Karray
authors.forename: Imen
authors.initials: I
authors.lastname: Ben Dhifallah
authors.forename: Kawther
authors.initials: K
authors.lastname: Ben Abdelghani
authors.forename: Imed
authors.initials: I
authors.lastname: Ben Ghorbel
authors.forename: Monia
authors.initials: M
authors.lastname: Khanfir
authors.forename: Habib
authors.initials: H
authors.lastname: Houman
authors.forename: Kamel
authors.initials: K
authors.lastname: Hamzaoui
authors.forename: Leith
authors.initials: L
authors.lastname: Zakraoui
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000208:ethnology* / Q000235:genetics*; D001528:Behcet Syndrome / Q000208:ethnology* / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D018167:Receptors, Calcitriol / Q000235:genetics*; D012727:Sex Characteristics; D014416:Tunisia
chemical_list: D018167:Receptors, Calcitriol