The RET gene codes for a protein that is crucial in the normal development of nerve cells as well as normal kidney development. Many mutations in this gene lead to Multiple Endocrine Neoplasia type 2. This condition leads to development of tumors in hormone producing glands, causing an increased risk for thyroid cancer. This is a result of the mutation causing an overactive protein, which leads to increased cell growth and division. This condition is inherited in an autosomal dominant manner, meaning each first degree relative (parent, child, and sibling) of an individual with this condition has a 50% chance of inheriting the disease causing mutation.