Here, we review recent advances in a gene that encodes another such protein, plant homeodomain finger protein 6 (PHF6), which possesses two chromatin-binding zinc finger domains and has been implicated in the Börjeson–Forssman–Lehmann X-linked intellectual disability syndrome (BFLS), T-cell acute lymphoblastic leukemia (T-ALL), and acute myeloid leukemia (AML) [9,10,11]. Here, PHF6 is linked to acute lymphoblastic leukemia.