A specific biomarker in glioma, Isocitrate Dehydrogenase (NADP(+)) 1 (IDH1), is found in more than 80% of secondary glioblastomas and only 5% of primary glioblastoma, implying that, at least in some conditions, genetic background (e.g., tumor malignancy indicator and IDH1) may be an optimal biomarker for the recognition of certain glioma subtypes [15,16]. The gene discussed is IDH1; the disease is glioma.