PRDM9 and diffuse large B-cell lymphoma: It is important to note that some of the most critical genetic alterations specifically detected in GCB DLBCL cases to date were the point mutations affecting the oncogenic histone methyltransferase EZH2 on the Tyr641 residue in 21.7% of GCB DLBCL cases (Morin et al., 2010) (Figure 1E).