Somatic CSF3R mutations are uncommon in AML and are associated with additional genetic alterations in transcription factors including double mutated CCAAT/enhancer binding protein α (CEBPAdm), core-binding factors (RUNX1-RUNX1T1 and CBFB-MYH11) and rarely NPM1 [10, 14–16]. The gene discussed is CBFB; the disease is acute myeloid leukemia.