While EZH2 is mutated at multiple sites in hematopoietic neoplasms, the Y646 amino acid is recurrently and significantly mutated in 7–22% of follicular lymphoma (FL) cases, with up to 40% of the mutations specifically a Y646H alteration [19]. The gene discussed is EZH2; the disease is hematopoietic and lymphoid cell neoplasm.