IFIH1 and psoriasis: Upon multiple logistic regression analyses for the presence of PsA, we found significant associations with psoriasis severity (OR: 2.14, 95%CI: 1.46–3.16), female sex (OR: 1.63, 95%CI: 1.12–2.38), and the IFIH1/MDA5 rs1990760 TT genotype (OR: 1.62, 95%CI: 1.11–2.37), while the HLA- Cw6 allele was protective (OR: 0.65, 95%CI: 0.44–0.95).