What are the genetic changes related to familial isolated pituitary adenoma ?
FIPA can be caused by mutations in the AIP gene. The function of the protein produced from this gene is not well understood, but it is thought to act as a tumor suppressor, which means it helps prevent cells from growing and dividing in an uncontrolled way. Mutations in the AIP gene alter the protein or reduce the production of functional protein. These changes likely impair the ability of the AIP protein to control the growth and division of cells, allowing pituitary cells to grow and divide unchecked and form a tumor. It is not known why the pituitary gland is specifically affected or why certain types of pituitary adenomas develop.  AIP gene mutations account for approximately 15 to 25 percent of cases of FIPA. Somatotropinomas are the most common type of tumor in these individuals. The tumors usually occur at a younger age, often in childhood, and are larger than FIPA tumors not caused by AIP gene mutations. The other genetic causes of FIPA are unknown.