Neurofibromatosis (NF) is a genetic disorder of the nervous system which causes tumors to form on the nerves anywhere in the body at any time. This progressive disorder affects all races, all ethnic groups and both sexes equally. NF is one of the most common genetic disorders in the United States (one in every 2500 births). Symptoms of Neurofibromatosis NF-1 is more common and is characterized by multiple (more than 5) tan patches on the skin (café-au-lait spots), freckles in the groin or armpit, nodules within the iris of the eyes, skin neurofibromas (small, rubbery skin lesions), bone defects, and visual disorders. Learning disabilities. Large tumors called plexiforms. Children with NF-1 are susceptible to neurologic complications including masses in the brain and spinal cord. NF-2 accounts for only 10 percent of all cases and is characterized by bilateral acoustic neuromas (masses around the eight cranial nerve in the brain) which causes hearing loss, facial weakness, headache, or unsteadiness. Café-au-lait spots and skin neurofibromas are much less common. Brain tumors and lens abnormalities (in the eye) may also occur. Thanks for giving. Any questions email debbi@run4nf.org