It is known that EZH2 is overexpressed in a variety of malignancies including some types of lymphomas, and gain-of-function mutations involving Tyr646 (previously Tyr641), Ala682 (previously Ala677) and Ala692 (previously Ala687) have been reported for this gene, resulting in increased tri-methylation of H3K27 [5–10]. This evidence concerns the gene EZH2 and lymphoma.