NF2 is a rare genetic condition that causes benign (non-cancerous) tumours to develop on the nerves, typically affecting the nervous system (brain and spine) and on peripheral nerves. The most common tumours in NF2-related schwannomatosis are called vestibular schwannomas on the nerve that carries sound and balance information from the inner ear to the brain (the eighth cranial nerve). Schwannomas are tumours that arise from the Schwann cells, which are the cells that produce the insulating myelin sheath covering nerves.

In NF2 these tumours often affect both ears and may lead to partial or complete hearing loss. NF2 can also cause schwannomas to develop on other nerves in the brain and spine or nerves in other places in the body, including on the skin. People with NF2 can also develop other tumours, including meningiomas (tumours in the lining of the brain and spinal cord), ependymomas (tumours that develop from cells lining the ventricles of the brain and centre of the spinal cord).

Most NF2 tumours are slow-growing and may cause minimal problems for years. Although they are non-cancerous their position may produce significant symptoms

Birth incidence of NF2 is approximately one in 25,000–33,000 worldwide, women and men are equally affected. The number of people affected in UK at a particular point in time is estimated to be 1 in 60,000.

Inherited From Parent- In half of all cases of NF2, the faulty gene is passed from a parent to their child. We have two copies of the genes in our body, one from each parent, including the NF2 gene. In NF2 it only takes a faulty gene in one copy of the gene to cause the condition; the second copy of the gene from the other parent will not have a fault and is working correctly. This is called an autosomal dominant pattern of inheritance. In general, a parent with an autosomal dominant disorder (such as NF2) has a 50% chance of passing along the condition to a child.

Autosomal Dominant Inheritance (https://www.jnetics.org/jewish-genetic-disorders/dominant-disorders)

Spontaneous NF2- In the other 50% of the people with NF2, the faulty gene appears to develop spontaneously, with them being the first person in their family to be diagnosed. This is referred to as sporadic or de novo occurrence.

NF2 is a variable and unpredictable condition affecting different people in different ways.

NF2-related schwannomatosis is caused by a pathogenic variant (a gene change that causes the gene to stop working correctly) in the NF2 gene located on chromosome 22

• Vestibular Schwannomas – The most common tumours in NF2 are called vestibular schwannomas which develop on the nerve that carries sound and balance information from the inner ear to the brain (the eighth cranial nerve). Having vestibular schwannomas on both hearing and balance nerves is the hall mark feature of NF2.

• Other Schwannomas- NF2 can also cause schwannomas to develop on other nerves in the brain and spine or nerves in other places in the body, including on the skin.

• Meningiomas – These are tumours in the lining of the brain and spinal cord. They occur in about 80% of people with NF2-SWN at some point in their lifetime but don’t always cause noticeable symptoms. Symptoms of meningiomas can include headaches, seizures, blurred vision, weakness, or numbness. Many meningiomas in people with NF2 never require treatment, but they are often monitored by MRI scans. Surgery is the primary treatment for meningiomas.

• Ependymomas– Tumours that develop from cells lining the ventricles of the brain and centre of the spinal cord. Spinal ependymomas may cause pain, sensory changes, or weakness but are most commonly asymptomatic. If needed, surgery is the primary treatment for ependymoma, although other treatments, such as radiation therapy or chemotherapy, may occasionally be considered.

Most NF2 tumours are slow-growing and may cause minimal problems for years. Although they are non-cancerous their position may produce significant symptoms.