Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Multiple endocrine neoplasia type 1 ?
    ### Response:
    Multiple endocrine neoplasia, type 1 (MEN1) is an inherited condition that causes tumors of the endocrine system (the body's network of hormone-producing glands). People affected by MEN1 typically develop tumors of the parathyroid gland, the pituitary gland, and the pancreas, although other glands may be involved as well.
    