ABL1 and acute lymphoblastic leukemia: They include parameters identified at diagnosis, such as: age, white blood cell count (WBC), the presence of translocations t(9;22)/BCR-ABL, t(4;11)/MLL-AF, or both, (further referred to as ‘fusion genes’), and factors assessed early during therapy, such as ALL blast count after 8 days of prednisone treatment (prednisone response) and bone marrow morphology (M1, M2, M3) assessed at day 15 and day 33.