The NF2 gene provides instructions for the production of a protein called merlin, also known as schwannomin. This protein is made in the nervous system, particularly in specialized cells that wrap around and insulate nerves (Schwann cells).
Merlin is believed to play a role in controlling cell shape, cell movement, and communication between cells. To carry out these tasks, merlin associates with the internal framework that supports the cell (the cytoskeleton). Merlin also functions as a tumor suppressor protein, which prevents cells from growing and dividing too fast or in an uncontrolled way.
More than 200 mutations in the NF2 gene have been identified in people with neurofibromatosis type 2. These mutations are often inherited from an affected parent and occur in all of the body's cells. About 90 percent of NF2 mutations result in an abnormally shortened version of the merlin protein. This short protein cannot perform its normal tumor suppressor function in cells. Research suggests that the loss of merlin allows cells, especially Schwann cells, to multiply too frequently and form noncancerous tumors. The most common tumors in neurofibromatosis type 2 are vestibular schwannomas, which develop along the nerve that carries information from the inner ear to the brain. Other tumors affecting the nervous system also occur in people with this condition.
Some gene mutations are acquired during a person's lifetime and are present only in certain cells. These changes, which are known as somatic mutations, are not inherited. Somatic mutations in the NF2 gene are involved in the development of several types of tumors, both noncancerous (benign) and cancerous (malignant).
Somatic mutations in the NF2 gene have been associated with a disorder called schwannomatosis that is similar to neurofibromatosis type 2. This condition is characterized by the development of multiple noncancerous tumors called schwannomas. These tumors may develop in nerves throughout the body; however, people with schwannomatosis do not develop the vestibular schwannomas characteristic of neurofibromatosis type 2. Although NF2 mutations are commonly found in tumors in people with schwannomatosis, researchers do not believe that these mutations cause the disorder. Scientists are working to identify other genetic changes that are responsible for the development of these tumors.
Loss or inactivation of the NF2 gene is also associated with a common type of brain or spinal cord tumor called a meningioma. These tumors form in the meninges, which are the thin layers of tissue that cover and protect the brain and spinal cord. Most meningiomas are benign; only a very small percentage of meningiomas become malignant.
Mesotheliomas are cancerous tumors that can arise in the lining of the lung and chest cavity (pleura) or the lining of the abdomen (peritoneum). These aggressive tumors are often associated with long-term exposure to asbestos. Researchers have determined that loss or inactivation of the NF2 gene occurs in approximately half of all cases of mesothelioma.
- Moesin-Ezrin-Radixin-Like Protein
- Neurofibromatosis 2 Gene Product
- Neurofibromatosis Type 2 Protein
- Neurofibromin 2
- neurofibromin 2 (bilateral acoustic neuroma)
- neurofibromin 2 (merlin)