Genetics Northern California

Neurofibromatosis 2

Neurofibromatosis 2 (NF2) is characterized by tumors of the brain and spinal cord. Tumors on both of the auditory nerves, which affect hearing, are the hallmark of NF2. These tumors are called vestibular Schwannomas.  Hearing loss beginning in the teens or early twenties is generally the first symptom.  It occurs in about 1 person out of 25,000 people.

Cause
NF2 is caused by a change (mutation) in a specific gene called NF2, located on chromosome 22.

Diagnosis
Genetic testing is not needed to make a diagnosis of NF2. The diagnosis of NF2 may be made if the following are present:

  • Tumors on the cranial nerves that affect hearing.  These are called vestibular schwannomas  (formerly called acoustic neuromas). They are detected by either CT (computed tomography) scan or MRI (magnetic resonance imaging).

    OR

  • A family history of NF2 in a parent, child, brother, or sister, PLUS a unilateral vestibular schwannoma occurring at less than 30 years of age, or a meningioma, glioma, schwannoma, or childhood cataract.

Inheritance
Neurofibromatosis, type 2 is inherited in an autosomal dominant pattern. In general, "autosomal dominant" means that the condition occurs equally in males and females, and that there is a 50% chance for the gene to be passed to a child. Therefore, individuals who have a diagnosis of NF2, have a 50% chance (in each pregnancy) to have a child with the same condition.

NF2 can sometimes happen for the first time in a family because of a new genetic change, also called a "spontaneous mutation”. This random change happens when the sperm or egg cell is being formed. In these families, neither parent is affected. This happens in about half of all NF2 cases.

Treatment/Services
Hearing: For those with NF2, periodic hearing testing is necessary to monitor the status of hearing and hearing loss.  Periodic eye exams are also necessary, as patients with NF2 can develop cataracts or optic tumors.  People with NF2 should be followed by a neurologist or neurosurgeon, in addition to their primary provider.

Tumors: The primary treatments for NF2 are therapies and accommodations for hearing loss and disability. Surgery and/or radiation may slow the progression of tumors, and may be recommended for some individuals.