Conventional and molecular cytogenetic analysis showed 5 (1.1%) out of 452 CML cases bearing additional chromosomal rearrangements concomitant to the generation of the 5'BCR/3'ABL1 fusion gene (Table 1; Fig. 1G, H). The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.