IDH1 and diffuse astrocytoma: The most common molecular alterations are mutations of the TP53 tumor suppressor gene at 17q13.1 in about 60% of cases as well as the just recently identified codon 132 mutations of the isocitrate dehydrogenase 1 (IDH1) gene in about 70% of diffuse astrocytomas [8–10] (Figure 1).