All four RUNX1-mutated cases presented two mutations, mainly of founding type (Table 3): three AUL patients (patients 2, 11, and 12) and one patient (patient 9) with a MPAL B/myeloid bilinear NOS whose immunophenotype profile was a mixture of an AML with minimal differentiation and a B-cell acute lymphoblastic leukemia (B-ALL) (Table 1). The gene discussed is RUNX1; the disease is acute lymphoblastic leukemia.