title: Determination of IL-23 receptor gene polymorphism in Iranian patients with ankylosing spondylitis.
abstract: BACKGROUND
  The result of recent genome-wide association studies revealed that, in addition to HLA-B27, a few non-HLA genes are associated with susceptibility to ankylosing spondylitis (AS) in Caucasian populations. According to these studies, IL-23R is one of the genes that is associated with AS. In this study, we evaluated five important single nucleotide polymorphisms (SNPs) of the IL-23R gene which confers susceptibility to AS, and its effects on the severity of the disease in HLA-B27 positive and negative patients and several subtypes of HLA-B27.
  
  
  METHODS
  The study population consisted of 294 AS patients and 352 age-, sex-, and ethnicity-matched healthy controls. All patients were examined by rheumatologists, and met modified, New York criteria for the disease. Five SNPs (rs1004819, rs11209032, rs1495965, rs11465804, and rs1004819) of the IL-23R gene were genotyped using the Real-Time PCR TaqMan genotyping method.
  
  
  RESULTS
  We found that only rs1004819 has a significant association with AS, and that the remaining four SNP alleles are not associated with AS. Also, there was no association between these five polymorphisms and BASDAI, BASFI, and BASMI indices. Two haplotypes, ACGAT and ACGAG, were found to be associated with the heritability of AS. In addition, two significant, protective diplotypes (D8, GCGAG/GTGGG ; and D9, ACGAG/GCGAG) were discovered.
  
  
  CONCLUSIONS
  This study supported our previous findings regarding the differences between the genetic patterns of AS in Iranian patients compared with those in other parts of the world.
authors.affiliation: Molecular Immunology Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Daryabor
authors.affiliation: Rheumatology Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Mahmoudi
authors.affiliation: Rheumatology Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ahmadreza
authors.initials: A
authors.lastname: Jamshidi
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Keramat
authors.initials: K
authors.lastname: Nourijelyani
authors.affiliation: Molecular Immunology Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Aliakbar
authors.initials: A
authors.lastname: Amirzargar
authors.affiliation: Rheumatology Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Nooshin
authors.initials: N
authors.lastname: Ahmadzadeh
authors.affiliation: Hematology Department, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Elham
authors.initials: E
authors.lastname: Farhadi
authors.affiliation: Molecular Immunology Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Nicknam
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People / Q000235:genetics; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D015796:HLA-B27 Antigen / Q000145:classification / Q000235:genetics*; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D007223:Infant; D007492:Iran; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D018123:Receptors, Interleukin / Q000235:genetics*; D013167:Spondylitis, Ankylosing / Q000235:genetics*; D044465:White People / Q000235:genetics; D055815:Young Adult
chemical_list: D015796:HLA-B27 Antigen; C515500:IL23R protein, human; D012333:RNA, Messenger; D018123:Receptors, Interleukin
keywords: HLA-B27; IL23R; SNP; ankylosing spondylitis