Problems with cognition, however, are more common and more severe for patients with a primary brain tumor than for healthy participants, and neuropsychological functioning often is lower for patients with an isocitrate dehydrogenase (IDH) wild-type or high-grade glioma than those with an IDH-mutant or low-grade glioma (Noll et al., 2015; van Kessel et al., 2017, 2019). The gene discussed is IDH3A; the disease is central nervous system cancer.