In addition, activating mutations at Y641 amino acid in the EZH2 gene within the EZH2 catalytic SET domain are recurrently and significantly mutated in up to 40% of B-cell lymphomas [10], and particularly in approximately 13–22% of DLBCL [4,11,12]. The gene discussed is EZH2; the disease is B-cell non-Hodgkin lymphoma.