VARIANT FORMS OF PHILADELPHIA TRANSLOCATION IN 2 PATIENTS WITH CHRONIC MYELOID-LEUKEMIA

During a 4-year period (December 1990-December 1994), among other diag noses one hundred cases of chronic myeloid leukemia (CML) were analyze d in our department. We focused our attention on two cases with a vari ant form of Philadelphia translocation. Cytogenetic and molecular gene tic studies were performed to resolve the status of BCR and ABL in the bone marrow or peripheral blood cells of the two CML patients with co mplex translocations involving chromosomes 3, 9, 22 and 9, 12, 22 resp ectively. In the first case the presence of Ph chromosome was detected cytogenetically, BCR-ABL translocation was detected by Southern hybri dization. In the second case, only the PCR method showed BCR-ABL rearr angement. The second case, with a random variant form of Ph translocat ion, could be detected using different methods of clinical molecular g enetics.