SUMO4 rs237025 relates to activation of immune cells and contributes to the autoimmune response, including T1D, autoimmune thyroid disease, and rheumatoid arthritis (Tsurumaru et al., 2006), however, susceptibility of rheumatoid arthritis or juvenile idiopathic arthritis was not associated with rs237025 polymorphism in the English Caucasian population (Gibbons et al., 2005). Here, SUMO4 is linked to rheumatoid arthritis.