BCR and acute lymphoblastic leukemia: Germline IGH-V(D)J ALL were associated with poor treatment response, frequent IKZF1 deletions and genomic rearrangements such as DUX4-IGH, EPOR-IGH, BCR-ABL1, FOXP1-ABL1, EBF1-PDGFR-ß, or aCRLF2-IGH (Table 3).