Investigated the impact of the loss of the 9p region in gliomas. Showed CDKN2A HD was not predictive in IDH-mutant 1p/19q non-codeleted astrocytomas but was for IDH-wildtype gliomas. They did demonstrate. Heterozygous loss was associated with poor OS, but mRNA expression was not altered. This evidence concerns the gene IDH1 and glioma.