IDH2 and essential thrombocythemia: A total of 38 IDH mutations (19 IDH2 R140, 18 IDH1 R132 and one IDH2-R172) were described: five ET (0.8%), eight PV (1.9%), 13 PMF (4.2%), one post-PV/ET myelofibrosis (1%) and 11 blast-phase MPN (21.6%) [11].