We replicate the known exclusivity between 1p/19q codeletions and ATRX loss, where 1p/19q codeletion/ATRX retention is found in oligodendroglioma, but preserved 1p/19q and ATRX loss occurs in astrocytoma.81,95 A 19q deletion alone was also associated with TERT wildtype and, interestingly, could also be seen with ATRX loss in astrocytomas.98 We additionally reproduce the association of 1p/19q codeletion with EGFR amplification.102. The gene discussed is TERT; the disease is oligodendroglioma.