The system also classifies tumors that do not carry IDH mutations (IDH-wildtype) in the presence of other molecular features, such as Epidermal growth factor receptor (EGFR) amplification, TERT promoter mutation, or the gain of chromosome seven with loss of chromosome 10 (+7/-10) to grade 4 glioblastomas regardless of their histologic appearance [10]. The gene discussed is IDH1; the disease is glioblastoma.