Fig. 1

a Karyotype of the patient displaying the t(12;14)(q23.2;q32.3). Arrows mark the translocation breakpoint regions on the derivative chromosomes. Note that der(12) is duplicated, leading to a partial trisomy 12. b Karyotype evolution (about three years later). Additional aberrations include a del(3)(p21), monosomy 13 and add(17)(p11). For detailed information see also Table 1. c FISH with the Cytocell IGH Breakapart probe on metaphase and interphase nuclei. The normal chromosome 14 generates a red-green fusion fluorescence signal. Der(14) yields only a red fluorescence signal with the distal green-labeled probe being translocated on der(12). A second green fluorescence signal is present due to the der(12) duplication. On the upper right side, a normal interphase with two red-green fusion signals is shown, next to an interphase bearing the translocation (lower right). A white arrow marks the fusion signal from the normal chromosome 14