Due to recent evidence that it may be involved in the pathogenesis of some subsets of diffusely infiltrating gliomas it was considered by the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy (cIMPACT-NOW) panel in 2020 for possible inclusion in the diagnostic and grading criteria of IDH-mutant astrocytoma, however due to challenges in comparing between studies and lack of consensus on copy number variation (CNV) threshold, this feature was not endorsed at the time [15]. The gene discussed is IDH1; the disease is astrocytoma (excluding glioblastoma).