Additional genetic markers are considered potentially relevant for tumor classification, such as the concurrent gain of whole chromosome 7 and the loss of whole chromosome 10, and mutations in the telomerase reverse transcriptase (TERT) promoter that are strongly correlated with glioblastoma IDH-wild-type, while mutations of B-Raf proto-oncogene (BRAF) and H3.3 histone A (H3F3A) associated with alterations of X linked intellectual disability (ATRX) and tumor protein P53 (TP53) are common in pediatric GBM [16,17,18]. This evidence concerns the gene ATRX and glioblastoma.