Partial karyotypes of patient 34 demonstrating the loss of 17p by 2 successive translocations of JT1q21. FISH probes 1q12 (red), 1q21 (green), 18 centromere (aqua), and 18q23 telomere (yellow) and on chromosome 17, TP53 (green), and ERB2 (red) are shown. SKY classification colors are 1q (yellow), 17 (blue), and 18 (auburn). (A) Two cell lines were detected in this stemline and a new subclone with additional aberrations of JT1q12 . The first abnormal specimen showed 3 normal copies of 17 (left bracket) and a JT1q12 translocated to the telomere of 18q [der(1;18), right bracket]. (B) In the second specimen analyzed 20 months later, a subclone was identified in which a second whole-arm JT1q12 resulted in the loss of 17p (left bracket). In this subclone, an unexpected focal amplification of 18q23 was detected by SKY (right bracket, middle) and confirmed by FISH (right bracket, far right) indicating the simultaneous segmental CN gains of 18qter, 1q21, and loss of 17p.