IDH1 and glioblastoma: IDH1 gene expression (mean ± stdev) was significantly overexpressed in adult primary GBM (11.52 ± 0.59) compared to non-tumor (8.85 ± 0.27) in the TCGA-GBM dataset (Figure S1a; p-value = 5.4 × 10−16), as previously reported [10,19].