Neurofibromatosis Type 1 (NF1)
A rare genetic condition that causes brown spots and tumors on the skin, freckling in skin areas not exposed to the sun, tumors on the nerves, and developmental changes in the nervous system, muscles, bone, and skin.
Part of: Neurofibromatosis (NF)
About Neurofibromatosis Type 1 (NF1)
NF1 is the most common neurofibromatosis, occurring in 1 in 3,000 to 4,000 individuals in the United States. Although many affected people inherit the disorder, between 30 and 50 percent of new cases result from a spontaneous genetic mutation of unknown cause. Once this mutation has taken place, the mutant gene can be passed to succeeding generations.
What are the signs and symptoms of NF1?
To diagnose NF1, a doctor looks for two or more of the following:
six or more light brown spots on the skin (often called “café-au-lait” spots), measuring more than 5 millimeters in diameter in children or more than 15 millimeters across in adolescents and adults; two or more neurofibromas, or one plexiform neurofibroma (a neurofibroma that involves many nerves); freckling in the area of the armpit or the groin; two or more growths on the iris of the eye (known as Lisch nodules or iris hamartomas); a tumor on the optic nerve (called an optic nerve glioma) abnormal development of the spine (scoliosis), the temple (sphenoid) bone of the skull, or the tibia (one of the long bones of the shin); a parent, sibling, or child with NF1….Read more about Neurofibromatosis Type 1NIH – National Institute of Neurological Disorders and Stroke