Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Multiple endocrine neoplasia type 1 ?
    ### Response:
    What causes multiple endocrine neoplasia, type 1? Multiple endocrine neoplasia, type 1 (MEN1) is caused by mutations in the MEN1 gene. MEN1 is a tumor suppressor gene which means that it encodes a protein that helps keep cells from growing and dividing too rapidly or in an uncontrolled way.
    