STAT4 single nucleotide polymorphisms (SNPs) are known to be associated with an increased risk of autoimmune diseases, such as systemic lupus erythematosus (SLE), primary Sjogren’s syndrome (pSS), rheumatoid arthritis (RA), or thyroid disease [12], so an association with other less well-studied diseases is possible. This evidence concerns the gene STAT4 and rheumatoid arthritis.