IDH1 and glioblastoma: GBM, low-grade glioma (Yan et al., 2009), cholangiocarcinoma (Jiao et al., 2013), acute myeloid leukemia (AML) (Mardis et al., 2009), chondrosarcoma, and melanoma (Amary et al., 2011; Krauthammer et al., 2012) have all been linked to IDH1 mutations.