Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Neurofibromatosis type 1 ?
    ### Response:
    What causes neurofibromatosis type 1? Neurofibromatosis type 1 is caused by changes (mutations) in the NF1 gene. NF1 is a tumor suppressor gene, which means that it encodes a protein that stops cells from growing and dividing too rapidly or in an uncontrolled way.
    