Among those that clustered with IDH-wildtype glioblastoma, four of the six tumors were with the mesenchymal subclass (all of which had co-occurring CDKN2A homozygous deletion but only one with co-occurring ATRX mutation), one was with the MYCN subclass (which had focal high level MYCN amplification), and the remaining one was with the midline subclass (which had truncating SETD2 mutation). This evidence concerns the gene CDKN2A and glioblastoma.