Outcome of B-cell precursor ALL (BCP-ALL) differs by genetic subtype, i.e. ETV6-RUNX1, high hyperdiploid, and TCF3-PBX1 cases have favorable prognosis, whereas BCR-ABL1, and KMT2A-rearranged BCP-ALL is associated with an unfavorable treatment outcome3. The gene discussed is BCR; the disease is acute lymphoblastic leukemia.