IDH1 and low grade glioma: In the IDH-wildtype glioma group (i.e., glioblastoma, low-grade glioma MYB/MYBL1 and (anaplastic) pleomorphic xanthoastrocytoma), MGMT promotor was methylated in 29% (5/17) and unmethylated in 71% (12/17) of the cases.