Molecular diagnosis of chronic myeloid leukemia using a 3'bcr probe.

Chronic myeloid leukemia (CML) is characterized by the Philadelphia chromosome which results from a reciprocal (9; 22) translocation, with the protooncogene c-abl moving from chromosome 9 to 22 and juxtaposed to the proximal bcr. Breakpoints on chromosome 22 are localized within 5.8 kb of the breakpoint cluster region (bcr). We have assessed the feasibility of using a 3'bcr probe for molecular diagnosis of CML. Thirty patients with Ph chromosome negative or positive CML were studied by Southern blot. A bcr rearrangement was seen to be present in all but one patient with Ph+CML. A case of Ph negative CML showed a bcr rearrangement. We conclude that this technique is efficient for molecular diagnosis of CML.