RELA and ependymoma: Based on the methylation profiles, the ependymal classes include the known PFA and PFB groups, the previously described supratentorial RELA‐fusion‐positive ependymoma, and three new molecular classes consisting of supratentorial YAP1‐fusion‐positive ependymomas, a benign spinal ependymoma, and a class closely related to the histological group of myxopapillary ependymoma28.