Isocitrate dehydrogenase (IDH)-wildtype gliomas (gliomas that do not have mutations in the IDH genes), resembling glioblastomas, exhibit worse prognoses compared to diffuse IDH-mutated gliomas (IDH mutation confirmed on IHC), characteristic of lower-grade astrocytomas and oligodendrogliomas. The gene discussed is IDH1; the disease is astrocytoma (excluding glioblastoma).