CDKN2A and ependymoma: From a genetic standpoint, ST ependymomas with C11orf95‐RELA were reported to typically have abundant copy number changes; frequent changes were focal losses and gains on chromosome11q (including chromothripsis), losses involving chromosomes 3, 9 (often resulting in homozygous deletion of CDKN2A), 10, and 22, and gain of chromosome 1q (3, 29).