​The 2016 World Health Organisation Classification of Tumours of the Central Nervous System (CNS) requires the classification of CNS tumours using a broad range of molecular tests; accurate classification is essential for selection of appropriate treatment modalities. Detection of mutations in IDH1 and IDH2 assists the differential diagnosis of gliomas and provides key diagnostic and prognostic information: IDH mutation status is a definitive marker of secondary glioblastoma; astrocytomas and oligodendrogliomas can contain mutations in IDH1 or IDH2, whereas other CNS tumours usually do not contain these mutations.

 

IDH1 and IDH2 mutation analysis is carried out by NGSand pyrosequencing. The pyrosequencing assay detects and differentiates 5 different “hot spot” mutations within IDH1 and 6 different mutations within the IDH2 gene.  These regions account for 99.7% of reported mutations in the IDH1 and IDH2 genes.  For further details of the NGS assay, including regions assessed, click here.