A multilocus genetic study evidences the association of autoimmune-related genes with Psoriatic Arthritis in Italian patients.

Psoriatic Arthritis (PsA) is an immune-mediated rheumatic disease caused by the interaction between environmental factors and genetic predisposition. Many of the risk loci associated with PsA susceptibility are shared with other autoimmune diseases, suggesting an involvement of the same pathways in these diseases. We investigated the association between nine selected polymorphisms and PsA susceptibility and their possible role in the modulation of the disease activity. We analysed 163 patients with PsA and 298 age and sex-matched healthy subjects. Our results showed the associations of five polymorphisms with the disease development: rs33980500 (TRAF3IP2), rs6920220 (TNFAIP3), rs27524 (ERAP1), rs7574865 (STAT4) and rs1800872 (IL10). Patients carrying the variant allele of TRAF3IP2 polymorphism had a higher number of tender/swollen joints and a higher Disease Activity Index for PsA score. The multilocus genetic risk profile showed a higher probability to develop the disease in subjects with at least four risk alleles.