Neurofibromatosis Causes and Risk Factors
Neurofibromatosis is a genetic condition characterized by noncancerous tumor growths on nerve tissues. It can affect any part of the nervous system, including the brain, spinal cord and nerves. Although the tumors are almost always benign, certain types can progress into malignant peripheral nerve sheath tumors.
Currently, there is no cure for neurofibromatosis. Treatment generally focuses on managing the symptoms and preventing complications, such as hearing loss, vision loss, cardiovascular issues and tumor progression.
What causes neurofibromatosis?
The most common genetic disorder caused by a single gene, neurofibromatosis can be passed from parent to child in an autosomal dominant pattern. This means just one copy of the mutated gene from one parent can cause the condition. Therefore, a child who has one parent with a mutated gene has a 50% chance of inheriting the mutated gene. Neurofibromatosis can also result from a spontaneous gene mutation, which occurs in approximately 50% of cases.
Genes are encoded with instructions for cell growth and development. Mutated genes can lead to accelerated cell growth and cause the cells to live beyond their normal lifespan, creating an abundance of cells that bind together and form a tumor. Additionally, neurofibromatosis often affects the pigment-producing cells in the skin, which can cause light brown (café-au-lait) skin spots.
The types of neurofibromatosis are:
Neurofibromatosis type 1 (NF1)
The most common type of neurofibromatosis, NF1 usually appears in childhood due to a mutation in the NF1 gene on chromosome 17, which produces a protein (neurofibromin) that regulates cell growth. The mutated gene causes a loss of neurofibromin, leading to uncontrolled cell growth. Symptoms include café-au-lait skin spots and benign tumors (neurofibromas) that form on nerves under the skin.
Neurofibromatosis type 2 (NF2)
Typically diagnosed during during adolescence or early adulthood, NF2 results from a mutation in the NF2 gene on chromosome 22, which produces a protein (merlin) that suppresses tumors. The mutated gene causes a loss of merlin, leading to uncontrolled cell growth. A hallmark sign is the development of tumors on the auditory nerves, which often leads to hearing loss.
Schwannomatosis
Caused by a mutation in the SMARCB1 or LZTR1 tumor-suppressor gene, schwannomatosis is characterized by multiple tumors (schwannomas) on the coverings of peripheral nerves throughout the body, which can cause debilitating pain and neurological dysfunction.
What are the risk factors for neurofibromatosis?
Because neurofibromatosis is a genetic condition, it is not associated with controllable risk factors in the way most other neurological tumors are. The primary risk factor is family history; more specifically, having a parent who has neurofibromatosis. Researchers continue to investigate other possible risk factors, such as advanced paternal age and certain as-yet-unidentified environmental exposures.
NF1 and NF2 are risk factors for other neurological conditions:
- NF1 increases the risk of developing schwannomas, meningiomas and gliomas.
- NF2 increases the risk of developing meningiomas, vestibular schwannomas and spinal cord ependymomas.
Additionally, both NF1 and NF2 slightly increase the risk of developing cancerous peripheral nerve sheath tumors, which are diagnosed in approximately 10% of cases.
Frequently asked questions (FAQs) about neurofibromatosis causes and risk factors
The following FAQs-related article provides additional information about neurofibromatosis causes and risk factors:
Benefit from world-class care at Moffitt Cancer Center
The multispecialty team in Moffitt’s renowned Neuro-Oncology Program is actively involved in neurological research. Through extensive studies and clinical trials, we are continually working to gain a better understanding of neurofibromatosis and other related conditions. We take a bench-to-bedside approach, quickly transferring our research results from the laboratory to the clinic to directly benefit our patients.
If you would like to learn more about neurofibromatosis causes and risk factors, you can request an appointment with a specialist in our Neuro-Oncology Program by calling 1-888-663-3488 or submitting a new patient registration form online. We do not require referrals.
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