However, the most recent WHO classification of astrocytomas considers molecular characteristics that are representative within astrocytomas and this new classification of astrocytomas separates these tumors according to the status of enzyme isocitrate dehydrogenase (IDH): wildtype (IDHwt) or mutant (IDHmt) [2]. The gene discussed is IDH3A; the disease is astrocytoma (excluding glioblastoma).