MYCN and ependymoma: Comparison to the complete methylation reference group continued to show MYCN amplified ependymomas clustering as a unique group, away from all other classified central nervous system tumors including MYCN amplified glioblastomas, with the exception of case 4 from the CERN archive that clustered at the periphery of the mesenchymal glioblastoma cases (Fig. 2b and Supplemental Figure S1).