Approximately 40-70% of children with NF1 exhibit one or more forms of specific learning disabilities and 20-45% have the features of autistic spectrum disorder (ASD). Thus, NF1 represents a unique monogenic model to investigate cognitive, and behavioral abnormalities caused by a well characterized cancer-related signaling pathway(s). We have recently developed a series of NF1-associated disease models (e.g. ASD) using advanced genetic tools, including the mosaic analysis using double marker (MADM) system. We will extend our work from brain tumors into cognition- and behavior-related neuroscience areas.