PDGFRB and acute lymphoblastic leukemia: t(9;22) was successfully detected in the two Philadelphia-positive ALL samples (Figure 1D), both displaying the minor BCR breakpoint and juxtaposition of exon 1 in BCR to exon 2 in ABL1. Two ABL-class rearrangements involving PDGFRB were also identified, whereas a known RANBP2::ABL1 fusion was missing from the variant list for P047.