Figure 2
From: Genetic abnormalities detected in ependymomas by comparative genomic hybridisation
CGH profiles and FISH from case 38. Standard thresholds (A) imply a severely hypodiploid karyotype, but none of the profiles follows the mid-line. This is characteristic of intermediate ploidy cases, and FISH with centromere probes (B) confirms that there were two copies of chromosome 8 (green) in all cells and three copies of chromosome 17 (red) in many. Skewing the midline to the left to give a chromosome 8 profile midway between the gain and loss thresholds (i.e. normal) produces a profile (C) that implies gain of a large number of chromosomes, although distal 22q is still clearly lost. By this interpretation chromosomes 4 and 16 could have two extra copies compared to a single extra copy of the other gained chromosomes, or could be gained in all cells while a smaller proportion of cells have the other gains.
