Table of Contents
ISRN Dermatology
Volume 2014, Article ID 570178, 5 pages
Research Article

The Region Centromeric to HLA-C Is a Key Region for Understanding the Phenotypic Variability of Psoriatic Arthritis

1Rheumatology Department, Hospital Universitario Central de Asturias (HUCA), C/Celestino Villamil S/N, 33006 Oviedo, Spain
2Dermatology Department, HUCA, C/Celestino Villamil S/N, 33006 Oviedo, Spain
3Immunology Department, Histocompatibility Unit, HUCA, C/Celestino Villamil S/N, 33006 Oviedo, Spain
4Department of Functional Biology, IUOPA, University of Oviedo, C/Celestino Villamil S/N, 33006 Oviedo, Spain

Received 24 October 2013; Accepted 10 December 2013; Published 30 January 2014

Academic Editors: M. Schmitt-Egenolf and A. Zalewska

Copyright © 2014 Rubén Queiro et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


With the aim of clarifying the role of several polymorphisms around the HLA-C locus in the clinical expression of PsA, the distribution of several polymorphic markers and genes located around the HLA-C locus was analyzed in a well-established cohort of 110 patients with PsA, 50 patients with psoriasis alone, and 110 healthy controls. The frequency of these genes was also analyzed by PsA articular models, based on three main subgroups: oligoarthritis, polyarthritis, and spondylitis. Distal interphalangeal joint (DIP) involvement was associated with the presence of MICB-CA20 (OR 6.0, 95% CI: 1.58–22.69, ). HLA-DRB 07 was associated with oligoarticular forms of PsA (OR 4.1, 95% CI: 1.8–9.3, ). The spondylitic forms overexpressed the antigen HLA-B 27 (OR 5.7, 95% CI: 2.4–13.6, ). MICA-A5.1 showed association with polyarthritis (OR 3.7, 95% CI: 1.5–8.8, ). Genes telomeric to HLA-C were overexpressed in psoriasis but not in PsA subphenotypes. This study shows that the region centromeric to HLA-C is a key region that expresses not only disease risk genes but also genes that help explain the phenotypic variability of PsA.