The lymphoid transcription factor IKZF1, commonly referred to as Ikaros, is frequently deleted in BCP-ALL [199], and in BCR-ABL1 (Ph+) and Ph-like ALLs, IKZF1 deletions and mutations are particularly frequent, present in almost 85% [215] and 70%, respectively [201,216]. This evidence concerns the gene IKZF1 and acute lymphoblastic leukemia.