Further loss‐of‐function mutations were observed in the histone-Lysine N-Methyltransferase 2D (MLL2/KMT2D) gene in about 90% of FL and 30% of DLBCL patients (Morin et al., 2011; Pasqualucci et al., 2011b; Lohr et al., 2012). Here, KMT2D is linked to diffuse large B-cell lymphoma.