Genetically, ETP-ALL frequently associates with mutations in genes encoding epigenetic regulators (IDH1, IDH2, and DNMT3A), signaling factors (i.e., NRAS and FLT3), and transcription factors involved in hematopoietic and T-cell development (RUNX1, GATA3 and ETV6), whereas both activating NOTCH1 mutations and CDKN2A deletions co-occurring with oncogenic NOTCH1 mutations are rarely observed [26,27]. The gene discussed is NOTCH1; the disease is acute lymphoblastic leukemia.