Here, we show that knockdown of Myb in leukaemia cells harbouring either wild-type or Cter/Nter–mutant C/EBPα reverses the abnormal myeloid phenotype normally observed in leukaemia, whereas AML cells carrying biallelic Nter/Nter mutations exhibit persistence of the undifferentiated phenotype. This evidence concerns the gene CEBPA and acute myeloid leukemia.