Tuberous sclerosis complex (TSC) is a rare genetic condition that causes non-cancerous (benign) tumors in various organs of the body, including in the brain. It is also accompanied by patches of unusually light-colored skin, and facial angiofibromas, which are tumors on the face. Affected individuals carry a mutation in the TSC1 or TSC2 gene. It is common for individuals with TSC to exhibit lower intelligence quotient (IQ) along with neuropsychiatric or attention-deficit disorders.