ID4 and acute lymphoblastic leukemia: The ID4 gene similarly behaves as a tumour suppressor through epigenetic silencing in most cases of acute myeloid leukemia [14], while in a sub-group of B-cell precursor acute lymphoblastic leukemia, expression of the ID4 gene is deregulated by the recurrent t(6;14)(p22;q32) chromosomal translocation [15,16].