TYK2 and psoriasis: Furthermore, meta-analysis of GWAS demonstrated that some TYK2 variants are linked with autoimmune diseases, including systemic lupus erythematosus (SLE), type 1 diabetes, IBD, psoriasis, multiple sclerosis (MS), systemic sclerosis, and primary biliary cirrhosis, as well as ulcerative colitis (UC), inflammatory myopathies and Crohn’s disease (CD) [1,16].