IFNL1 and oligodendroglioma: With the notable exception of loci included in the oligodendroglioma-defining 1p/19q codeletion event (IRF3, JAK1, ISG15, IFNL1, and IFNL2), we found a general paucity of mutations, high-level amplifications, and/or deep deletions associated with ATRX mutations (Supplementary Fig. 2), indicating that the effects of glioma-associated molecular alterations like IDH mutation and ATRX deficiency are likely not mediated via genetic mutations or copy number variations.