According to the break within the Bcr locus (Quackenbush et al, 2000), three oncogenic BCR-Abl fusion proteins: p190, p210 and P230 can be formed and they all were found to be sufficient to generate leukaemia in humans and murine models (Daley et al, 1990; Huettner et al, 2000). Here, ABL1 is linked to leukemia.