In this subtype, one of the signature genetic changes is mutation of the NF1 tumor suppressor gene [17], which is intriguing, given the prior identification of ABCG1 as a uniquely upregulated transcript in GSCs originating from a mouse model of low-grade glioma harboring biallelic Nf1 gene inactivation [16, 26]. The gene discussed is NF1; the disease is central nervous system cancer.