Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) GRN-related frontotemporal dementia ?
    ### Response:
    GRN-related frontotemporal dementia is a progressive brain disorder that can affect behavior, language, and movement. The symptoms of this disorder usually become noticeable in a person's fifties or sixties, and affected people typically survive 6 to 7 years after the appearance of symptoms.
    