In support of ZEB1 mutations carrying out a pro-tumorigenic function, the top 10 genes which included well known contributors to both GBMs and low grade gliomas such as IDH1, TP53, NF1 and ZEB1 were for the most part mutually exclusive and strongly associated with missense or splice site mutations (Fig. 3a). This evidence concerns the gene NF1 and central nervous system cancer.