To exclude an a priori resistance to ABT-199 by mutations in ASXL1, RUNX1, TP53 or EZH2, we analysed gene expression data in an extended cohort of MDS patients (n = 90) with or without an adverse mutational profile and compared it to healthy controls (n = 110) (Figure 1). The gene discussed is EZH2; the disease is myelodysplastic syndrome.