LZTR1

More than 50 different mutations in the LZTR1 gene have been found in people with schwannomatosis, a disorder characterized by multiple noncancerous (benign) tumors called schwannomas that grow on nerves. This type of tumor arises from Schwann cells, which are specialized cells that normally form an insulating layer around the nerve.

LZTR1 gene mutations associated with schwannomatosis lead to production of an altered LZTR1 protein that is less able to control cell growth and division, which allows tumors to develop. It is unknown why these gene mutations are predominantly associated with schwannomas, instead of other types of tumor, in people with schwannomatosis.

It appears that mutations in the LZTR1 gene alone are not enough to trigger the development of schwannomas. Additional genetic changes (somatic mutations) that are acquired during a person's lifetime and are present only in certain cells may also be required for schwannomas to form.

Some people who have a mutation in the LZTR1 gene never develop tumors, which is a situation known as reduced penetrance.

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Mutations in the LZTR1 gene have also been found in a type of cancerous (malignant) brain tumor called glioblastoma. These mutations are classified as somatic and are present only in the cells that give rise to the tumor. Scientists believe that somatic changes in the LZTR1 gene, or a loss of this gene, are among the factors that allow certain brain cells to grow and divide uncontrollably to form a tumor.