IDH2 and astrocytoma (excluding glioblastoma): IDH1 mutations at R132 have been associated with astrocytomas, GBM, and oligodendrogliomas, and IDH2 mutations at R172 have been linked with gliomas (Dang et al., 2010; Yan et al., 2009).IDH1/2 have been linked to enhanced reductive carboxylation in hypoxia for de novo lipogenesis (Metallo et al., 2011).