In an effort to further characterize oligodendroglial tumors, we analyzed a set of 17 oligodendrogliomas and oligoastrocytomas by applying a comprehensive approach of genome-wide profiling by array comparative genomic hybridization (array CGH), expression analyses by transcriptome next generation sequencing (RNA-seq) and DNA Sanger sequencing for mutations in CIC, FUBP1 and IDH1/2. Here, IDH1 is linked to oligoastrocytoma.