Prevention of copy-number changes in RAD51-suppressed cells is confirmed by array CGH. To confirm the prevention of copy-number changes following RAD51 suppression in BAC cells, DNA samples from two independent experiments, which were analyzed by SNP arrays, were also analyzed by CGH assay using Agilent’s high density (1M) CGH arrays. (a) Representative CGH figure showing copy-number changes on chromosomes 1, 6 and 19, in control CS and RAD51-suppressed RS cells. With reference to the baseline genome, the amplifications (as red dots) and deletions (as green dots) acquired by CS and RS cells, are shown next to each chromosome. (b) For the experiment shown in panel (a), total numbers of copy-change events identified by SNP and CGH are presented as bar graphs. (c) Copy-change events identified by SNP and CGH in another independent experiment are shown. The number of copy-change events in control CS and RAD51-suppressed RS cells identified by SNP is consistent with those detected by CGH (R=0.99). A full colour version of this figure is available at the Oncogene journal online.