A few years later, the discovery of a specific defect in the enzymatic activity of the mitochondrial isocitrate dehydrogenase (IDH) [29,30,31] led to the tumour accumulation of 2-hydroxyglutarate (2-HG), further proving the importance of specific metabolites in tumorigenesis starting the oncometabolites era. Here, IDH1 is linked to neoplasm.