IDH1 and glioma: Mutations of the isocitrate dehydrogenase (IDH1) gene has been shown to be a marker of oncogenesis and is one of the most specific biomarkers in the diagnostic classification of secondary GBM (Dang et al., 2010) Gliomas with mutated IDH have improved prognosis compared to gliomas with wild-type IDH and are detected by immunohistochemistry and magnetic resonance (MR) spectroscopy (Cohen et al., 2013).