The transplantation of these o-GSCs into the brainstems of 3-week-old NF1+/- mice yielded optic gliomas within 6 months, but not transplantation of o-GSCs into brainstems of immunocompromised athymic mice, emphasizing the need for NF1+/- local microenvironment in glioma formation (83). The gene discussed is NF1; the disease is central nervous system cancer.