Therefore, we tested the apoptotic effect of ABT-199 in primary BM samples of 31 MDS/sAML patients presenting with mutations in ASXL1, RUNX1, TP53 or EZH2 in comparison to 21 non-mutated MDS samples (Table 1A and Supplementary Table 1). Here, RUNX1 is linked to myelodysplastic syndrome.