Significant focal copy number changes as identified by GISTIC analysis (q-value of < 0.001) occurred on chromosomes 3, 9, 16 and 22 in regions that contain tumour suppressor genes, BAP1 (chr3), CDKN2A (chr9) and NF2 (chr22) (Fig. 1F). This evidence concerns the gene CDKN2A and neoplasm.