IDH1 and neoplasm: Amongst this data, gene amplification at chromosome 4q12 has been reported in 74/463 (16%) cases assessed by array-based comparative genomic hybridisation (aCGH) [5], and is linked to a subclass of tumours associated with a younger age at diagnosis, Proneural gene expression signature, IDH1 mutation, and a CpG island methylator phenotype [4], [6].