IKAROS controls gene transcription through the interaction with HDACs and chromatin-remodeling complexes, as Mi-2/NuRD and SWI/SNF, at canonical GGAAA binding sequences and pericentromeric heterochromatin alterations in the Ikzf1 gene was shown in 83.7% of the patients affected by Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL), consisting of haplo-insufficiency or a complete loss of expression, or in the presence of DN isoforms. The gene discussed is SMARCA1; the disease is acute lymphoblastic leukemia.