title: Implications of the diversity of class I HLA associations in psoriatic arthritis.
abstract: We sought to validate and extend the findings of a 282 psoriatic arthritis patient cohort from Dublin using a 219 patient cohort from Bath. The central finding of this study was that several structurally unrelated HLA alleles, including B*08:01:01, B*18:01:01, B*27:05:02, B*55:01:01 and C*06:02:01, were found to be significantly associated with particular phenotypic features of psoriatic arthritis, implying that the clinical diagnosis of psoriatic arthritis designates a genetically heterogeneous subset of individuals. Radiographic sacroiliitis was associated with either B*08:01:01, or B*27:05:02 with implications about the role of MHC molecules in an adaptive immune response. There are also implications for psoriatic arthritis diagnostic criteria since some disease features used in the criteria are under genetic control. These findings have important implications for understanding the role of MHC alleles in directing the adaptive immune response to mediate the inflammation responsible for psoriatic arthritis.
authors.affiliation: Columbia University, College of Physicians and Surgeons, Division of Rheumatology, United States. Electronic address: rjw8@columbia.edu.
authors.forename: Robert
authors.initials: R
authors.lastname: Winchester
authors.affiliation: Columbia University, College of Physicians and Surgeons, Division of Rheumatology, United States.
authors.forename: Jon
authors.initials: J
authors.lastname: Giles
authors.affiliation: Royal National Hospital for Rheumatic Diseases, Rheumatology Department, Bath, UK; Cambridge University Hospitals NHS Foundation Trust, Rheumatology Department, Department of Rheumatology, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: Deepak
authors.initials: D
authors.lastname: Jadon
authors.affiliation: Department of Rheumatology, St. Vincent's University Hospital and Conway Institute, University College Dublin, Dublin, Ireland; University Hospital Kerry, Kerry, Ireland.
authors.forename: Muhammed
authors.initials: M
authors.lastname: Haroon
authors.affiliation: Royal National Hospital for Rheumatic Diseases, Rheumatology Department, Bath, UK.
authors.forename: Neil
authors.initials: N
authors.lastname: McHugh
authors.affiliation: Department of Rheumatology, St. Vincent's University Hospital and Conway Institute, University College Dublin, Dublin, Ireland.
authors.forename: Oliver
authors.initials: O
authors.lastname: FitzGerald
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D015535:Arthritis, Psoriatic / Q000235:genetics* / Q000276:immunology*; D005260:Female; D015235:HLA-B Antigens / Q000235:genetics*; D015236:HLA-C Antigens / Q000235:genetics*; D006801:Humans; D007494:Ireland; D008297:Male; D008875:Middle Aged; D006113:United Kingdom
chemical_list: D015235:HLA-B Antigens; D015236:HLA-C Antigens
keywords: Adaptive immune response; Genetic heterogeneity; HLA associations; Phenotypic heterogeneity; Psoriatic arthritis