In 2008, it was reported that ITP patients had significantly lower mRNA expression of DNA methyltransferase 3A and 3B (DNMT3A and DNMT3B) in peripheral blood mononuclear cells, and increased plasma SAH concentration when compared with healthy controls, indicating aberrant DNA methylation status in ITP (82). The gene discussed is DNMT3B; the disease is autoimmune thrombocytopenic purpura.