Also, the WHO CNS5 classifies tumors with alterations in H3F3A to the pediatric-type diffuse high grade gliomas family as they have significantly worse outcomes, and tumors with homozygous CDKN2A/B deletion as having the highest malignancy grade in the group of diffuse, IDH-mutant astrocytomas (135, 137). The gene discussed is IDH2; the disease is astrocytoma (excluding glioblastoma).