Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) autosomal recessive spastic ataxia of Charlevoix-Saguenay ?
    ### Response:
    Autosomal recessive spastic ataxia of Charlevoix-Saguenay, more commonly known as ARSACS, is a condition affecting muscle movement. People with ARSACS typically have abnormal tensing of the muscles (spasticity), difficulty coordinating movements (ataxia), muscle wasting (amyotrophy), involuntary eye movements (nystagmus), and speech difficulties (dysarthria).
    