Analysis of the breakpoints in translocation (15;17) observed in 4 patients with acute promyelocytic leukemia

Four patients with acute promyelocytic leukemia (APL) and the chromosomal translocation (15;17) are described in detail. One of the patients presented with the microgranular variant form of APL and the standard translocation. Another patient is the third reported case with isochromosome formation of the 17q-derivative. Use of high resolution culture technique with methotrexate treatment allowed us to define the breakpoints at 15q2200 and 17q12.