FISH-microdissection of rearranged maternal chromosomes. The origin of chromosomes was identified by whole chromosome painting probes (WCP): chromosome 7 (ice blue), chromosome 10 (purple) and chromosome 9 (yellow) are displayed and measured by the fluorescence and FISH Imaging System ISIS 3 (Metasystems, Altlußheim, Germany). The rearranged chromosomes of the balanced rearrangement are marked with circles. On the left side normal chromosomes are displayed hybridized with the labelled DNA from the microdissected chromosomes (reverse painting). Statistical analysis of the measured chromosome paintings was done using Microcal™ OriginR 6.0 (Microcal, Northampton,MA). On the very left side ideograms of the reverse painted derivative chromosomes are displayed to allow breakpoint designation.