SNPs in STAT4 have been reported as risk factors for the development of autoimmune diseases, including RA, SLE, lupus nephritis (LN), type 1 diabetes (T1D), psoriasis, inflammatory bowel disease (IBD), Behçet’s disease (BD), Sjögren’s syndrome (SS), systemic sclerosis (SSc), primary biliary cirrhosis (PBC), and other diseases (Table 1). This evidence concerns the gene STAT4 and systemic sclerosis.