In order to facilitate the distinction of EZH2 wild-type from EZH2 mutant-type DLBCL, the group around Dubois investigated the immunohistochemical expression of EZH2 and mono-, di-, and tri-methylated H3K27 in relation to the EZH2 somatic mutational status. The gene discussed is EZH2; the disease is diffuse large B-cell lymphoma.