Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) ataxia-telangiectasia ?
    ### Response:
    Ataxia-telangiectasia is a rare inherited disorder that affects the nervous system, immune system, and other body systems. This disorder is characterized by progressive difficulty with coordinating movements (ataxia) beginning in early childhood, usually before age 5.
    