(A) Amplified ABL oncogenes in patient no. 4, showing four to six signals in interphase cells. Some signals are slightly out of focus. (B) Amplified ABL oncogenes in patient no. 1, representing five copies in one metaphase (small arrows). Two homologues of chromosome 9 are stained with a spectrum orange WCP9 probe (large arrows). (C) Amplified chromosomal segment containing CD3-MLL genes from patient no. 4. Four chromosomal segments of 11q23 were found in one metaphase (small arrows): one was on the normal chromosome 11 (arrowhead), one on a derivative 12 (large arrow), and two on the isochromosome 11q10 (star). Chromosome 11 is painted in red with rhodamine and the CD3 gene in green with fluorescein.