EZH2 inactivating deletions, frameshift, and nonsense and missense mutations have been identified in parts of T-cell acute lymphocytic leukemia, myeloproliferative neoplasms, and myelodysplastic syndromes (Ernst et al., 2010; Nikoloski et al., 2010; Ntziachristos et al., 2012). The gene discussed is EZH2; the disease is myeloproliferative disorder.