ATRX mutations have been shown to inhibit homologous recombination repair in cell lines [79–81], are linked to PARP inhibitor sensitivity in patient-derived xenografts [82], are associated with higher PARP1 expression in clinical glioblastoma tumors [83], and have shown sensitivity to DNA-damaging treatment in pediatric high-grade glioma patients [84]. Here, ATRX is linked to glioblastoma.