ASSOCIATION STUDY OF GENETIC RISK VARIANTS FOR PSORIASIS IN A LARGE COHORT OF PSORIATIC ARTHRITIS, PSORIASIS AND CONTROLS OF THE SPANISH POPULATION AND ASSOCIATION WITH RELEVANT CLINICAL SUBPHENOTYPES

Background: Psoriatic Arthritis (PsA) is a complex disease with a substantial genetic risk component (first-degree relative risk ∼55). Recently, Genomewide Association Studies (GWAS) have expanded the number of risk loci for Psoriasis (Ps) in >20 new loci. Objectives: We have studied the association of Ps risk loci in PsA and purely cutaneous Ps (PsC). We have also analyzed the genetic association with several subphenotypes of clinical relevance. Methods: Loci showing the strongest statistical evidence of association to Ps were selected (n=32). The SNP having the highest statistical evidence was genotyped using Taqman technology in a cohort of n=955 PsA, 1,050 PsC and 1,497 hypernormal controls of the Spanish population. According to each subphenotype variable, the genetic association was performed using the chi-square test, logistic regression or linear regression. Results: We have replicated the association to COG6 and SERPINB8 loci with Ps for the first time in a Caucasian population. We have identified, for the first time, an association of PsA with variation at IFIH1, DPP6 and COG6. Analyzing the association with other clinically relevant subphenotypes we have identified a strong association of LCE3D locus with the severity of cutaneous affection. We have also found a significant association of IL1RN gene with nail disease. Conclusions: Our findings show that common genetic variants associated to a complex phenotype like PsV influence PsA as well as different subphenotypes of high clinical relevance. Disclosure of Interest: None DeclaredCitation: Annals of the Rheumatic Diseases, volume 71, supplement 3, year 2012, page 638Session: Genomics, genetics and epigenetics of rheumatic diseases (Abstracts accepted for publication )