By contrast, RRAS1 mRNA expression was enhanced in CNS tumors, albeit not to the same extent as RRAS2. Given that unlike RRAS1 or RRAS3, RRAS2 can transform NIH-3 T3 cells [8-11], and in light of the low frequency of oncogenic mutations in classic Ras genes, we hypothesize that R-RAS2 overexpression is an important event in the transformation of neural cells, particularly those that do not carry oncogenic RAS mutations (database reference). The gene discussed is MRAS; the disease is central nervous system neoplasm.