Further evidence of the involvement of the c-abl oncogene in chronic myelogenous leukemia and acute lymphocytic leukemia.

In an attempt to further substantiate the involvement of the c-abl oncogene in the genesis of chronic myelogenous leukemia (CML) and acute lymphocytic leukemia (ALL), we performed in-situ hybridization with the c-abl probe on metaphase chromosomes of a healthy control, a karyotypically normal non-CML leukemia, three cases of CML with t(9;22), t(13;22) and t(3;9;22), one blast phase CML with t(9;22), Ph, + Ph, and one ALL with t(9;22), Ph, + Ph. The aberrant 9q could be cytogenetically identified in all cases except t(13;22). The molecular data clearly demonstrated the involvement of the c-abl in t(13;22) and the karyotype was revised to t(9;13;22). All patients, except the control, showed the altered c-able/bcr rearrangement that has been demonstrated in the Ph-chromosome from the standard t(9;22) translocation. These findings suggest that genomic diversities have important clinical differences in these two diseases. The amalgamation of information from cytogenetic and molecular data on cases where translocations are not precise or difficult to identify, will lead towards a deeper understanding of leukemias.