Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) mucopolysaccharidosis type III ?
    ### Response:
    Mucopolysaccharidosis type III (MPS III), also known as Sanfilippo syndrome, is a progressive disorder that mainly affects the brain and spinal cord (central nervous system).  People with MPS III generally do not display any features of the condition at birth, but they begin to show signs and symptoms of the disorder during early childhood.
    