Activating mutations in EZH2 have been observed in malignant B cell lymphomas [82,83]; however, loss of function mutations in EZH2 are frequently identified in patients with myelodysplastic syndrome (MDS) and MF [84] and loss of function is associated with drug resistance and adverse clinical outcome in hematologic malignancies [85,86,87]. Here, EZH2 is linked to myelodysplastic syndrome.