CLINICAL USE OF THE BCR ABL PROBE TEST IN THE EVALUATION OF CHRONIC MYELOID-LEUKEMIA PATIENTS/

CML is characterized by a reciprocal translocation between the abl and bcr genes on chromosomes 9 and 22 and is usually diagnosed by the pre sence of the Philadelphia (Ph-1) chromosome. However, the translocatio n may also occur without the appearance of the Ph-1 chromosome, In thi s study the diagnostic efficiency of the molecular hybridization assay was investigated in 227 patients using a probe specific for the bcr r egion of the gene, Gene rearrangements were observed in 96% of Ph-1-po sitive cases and in 92% of the patients in whom no Ph-1 chromosome cou ld be detected by karyotype analysis. By using peripheral blood the as say is easy to perform and superior in sensitivity. Thus, it is recomm ended that this assay should be routinely used as anadjunct to classic al cytogenetics.