Focal CNAs that are known to play roles in the origination and development of GBM and are described by the global pattern include amplifications of segments containing the genes MDM4 (1q32.1), AKT3 (1q44), EGFR (7p11.2), MET (7q31.2), CDK4 (12q14.1) and MDM2 (12q15), and deletions of segments containing the genes CDKN2A/B (9p21.3) and PTEN (10q23.31), that occur in 3% of the patients. Here, CDK4 is linked to glioblastoma.