The TET2 mutation frequencies in the different patient groups are MDS (6%-26%), CMML (20%-58%), primary and secondary AML (12%-32%), blastic plasmacytoid dendritic neoplasm (25%-54%), myeloproliferative neoplasms (MPNs) (2%-20%), B-cell (2%-12%) and T-cell (20%-83%) lymphomas, systemic mastocytosis (20-29%), and chronic myeloid leukemia (4%) [87]. This evidence concerns the gene TET2 and myelodysplastic syndrome.