We also measured IgM anti-H31–19K9me in JIA patients and other RD patients, including juvenile ankylosing spondylitis, Henoch-Schonlein purpura, idiopathic thrombocytopenic purpura, Kawasaki disease, mixed connective tissue disease, juvenile dermatomyositis and Behcet’s disease. The gene discussed is CD40LG; the disease is autoimmune thrombocytopenic purpura.