RUNX1 and precursor B-cell acute lymphoblastic leukemia: The translocation t(12;21)(p13;q22) generating ETV6/RUNX1 (TEL/AML1) fusion gene occurs in ~ 25% of childhood B‐cell precursor acute lymphoblastic leukemia (ALL) (Harbott, Viehmann, Borkhardt, Henze, & Lampert, 1997).