Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Mucopolysaccharidoses ?
    ### Response:
    The mucopolysaccharidoses are a group of inherited metabolic diseases in which a defective or missing enzyme causes large amounts of complex sugar molecules to accumulate in harmful amounts in the body's cells and tissues. This accumulation causes permanent, progressive cellular damage that affects appearance, physical abilities, organ and system functioning, and, in most cases, mental development.
    