To functionally assess the requirement for RUNX1 in leukemia, we depleted RUNX1 in vitro in four B-ALL cell lines and a control chronic myeloid leukemia (CML) cell line and monitored proliferation of leukemic cells over nine days (Supplementary Fig. 5d, red asterisks, and 7a, Supplementary Table 2). This evidence concerns the gene RUNX1 and chronic myelogenous leukemia, BCR-ABL1 positive.