We used Venn diagrams to visualize patterns of CNAs in the oncogene EGFR (7p11.2) and the tumor suppressor genes CDKN2A (9p21.3) and PTEN (10q23.31) (Although our data cannot determine whether CNAs affecting these genes are functionally targeting these genes or nearby ones, these are genes with known functional significance in gliomas). The gene discussed is EGFR; the disease is central nervous system cancer.