title: Endothelial nitric oxide synthase haplotype associations in biopsy-proven giant cell arteritis.
abstract: OBJECTIVE
  To assess the influence of endothelial nitric oxide synthase (eNOS) polymorphisms in the susceptibility to giant cell arteritis (GCA).
  
  
  METHODS
  We studied 57 patients with biopsy-proven GCA diagnosed at the Rheumatology Division of Hospital Xeral-Calde and 117 ethnically matched controls. Patients and controls were genotyped by PCR for a variable number tandem repeat polymorphism in intron 4, a T/C polymorphism at position -786 in the promoter region, and a polymorphism in exon 7 (298Glu/Asp or 5557G/T) of the eNOS gene.
  
  
  RESULTS
  No differences in allele or genotype frequencies for individual polymorphisms were observed between patients with GCA and controls. However, when haplotype frequencies for the combination of the 3 eNOS polymorphisms were estimated, a significant increase in the frequency of haplotype C/1/T and a significant decrease in the frequency of haplotype C/1/G were observed in GCA patients compared to controls (p = 0.04, OR 1.8, 95% CI 1.0-3.3; p = 0.02, OR 0.3, 95% CI 0.1-0.8, respectively).
  
  
  CONCLUSIONS
  Significant differences in eNOS haplotype frequencies between GCA patients and controls may indicate a role for these polymorphisms in the susceptibility to this condition.
authors.affiliation: Centre for Integrated Genomic Medical Research, University of Manchester, Manchester, UK.
authors.forename: Mahsa M
authors.initials: MM
authors.lastname: Amoli
authors.forename: Carlos
authors.initials: C
authors.lastname: Garcia-Porrua
authors.forename: Javier
authors.initials: J
authors.lastname: Llorca
authors.forename: William E R
authors.initials: WE
authors.lastname: Ollier
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Gonzalez-Gay
mesh_terms: D001483:Base Sequence; D001707:Biopsy, Needle; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D004198:Disease Susceptibility; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D013700:Giant Cell Arteritis / Q000235:genetics* / Q000473:pathology*; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D019001:Nitric Oxide Synthase / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D019001:Nitric Oxide Synthase