Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Crouzon syndrome ?
    ### Response:
    Crouzon syndrome is a genetic disorder characterized by the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face.  Many features of Crouzon syndrome result from the premature fusion of the skull bones.
    