Overexpression of CD70, DNMTs and MBD2. Hypomethylation of CD70 promoter in CD4+ T cells of ITP patients. CD70 transcription levels negatively correlated with methylation indices but positively correlated with DNMT1, DNMT3A, DNMT3B. The gene discussed is DNMT3B; the disease is autoimmune thrombocytopenic purpura.