Neurofibromin 1 (NF1), tuberous sclerosis complex (TSC1/TSC2), and phosphatase and tensin homolog (PTEN) are genes associated with neurological diseases with common autistic symptoms including neurofibromatosis (Rasmussen and Friedman, 2000), tuberous sclerosis (van Slegtenhorst et al., 1997), and Cowden/Lhermitte-Duclos syndrome (Pilarski and Eng, 2004). The gene discussed is TSC2; the disease is tuberous sclerosis.