This meta-analysis demonstrates that the STAT4 rs7574865 T allele confers susceptibility to SLE, RA, T1DM, systemic sclerosis (SSc), juvenile idiopathic arthritis (JIA), primary antiphospholipid syndrome (APS), inflammatory bowel diseases-ulcerative colitis (IBD-UC), autoimmune thyroid diseases, and psoriasis, supporting the hypothesis of an association between STAT4 gene polymorphism and subgroup of autoimmune diseases [15]. Here, STAT4 is linked to type 1 diabetes mellitus.