Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to familial isolated hyperparathyroidism ?
    ### Response:
    Familial isolated hyperparathyroidism can be caused by mutations in the MEN1, CDC73, or CASR gene.  The MEN1 gene provides instructions for producing a protein called menin. Menin acts as a tumor suppressor, which means it normally keeps cells from growing and dividing (proliferating) too rapidly or in an uncontrolled way.
    