PBX1 and acute lymphoblastic leukemia: The screen for JAK2 fusion genes was confined to 153 BCP-ALL cases, negative for sentinel BCP-ALL associated lesions (KMT2A-rearranged, BCR-ABL1, ETV6-RUNX1, TCF-PBX1, high hyperdiploid), as JAK2 translocations were previously reported in this group of patients [12, 13, 25].