CN signature 1 (CN-Sig-1), characterised by large segment sizes and low breakpoint frequency (0-2 breakpoints per chromosome arm), was the predominant signature and was higher in seminomas positive for mutations in KIT (p = 0.004) and RAS mutations (KRAS and NRAS combined, p = 0.07) (Fig. 7c), recapitulating the association of mutations in the RAS/MAPK signalling pathway with CN-Sig-1 reported in serous ovarian carcinomas27. The gene discussed is KRAS; the disease is seminoma.