Primary and recurrent gliomas as well as spinal metastases of patients with rare POLE/POLD1 variants were assessed with respect to features of polymerase proofreading defects by determining TMB and signatures of somatic mutations in glioma DNA as well as presence of multinucleated cells or enlarged nuclei and immune cell response in glioma sections. The gene discussed is POLD1; the disease is glioma.