Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) dystonia 6 ?
    ### Response:
    Dystonia 6 is one of many forms of dystonia, which is a group of conditions characterized by involuntary movements, twisting (torsion) and tensing of various muscles, and unusual positioning of affected body parts. Dystonia 6 can appear at any age from childhood through adulthood; the average age of onset is 18.
    