An 8q gain was detected in 13 tumors harboring IDH and TP53 mutations from 7 patients; tumors with an 8q gain consisted of 5 diffuse astrocytomas, 4 anaplastic astrocytomas, and 2 glioblastomas, IDH-mutant, whereas tumors without an 8q gain consisted of 17 diffuse astrocytomas, 10 anaplastic astrocytomas, and 3 glioblastomas, IDH-mutant (Table 2 and Figure 3A). Here, IDH1 is linked to diffuse astrocytoma.