Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) congenital central hypoventilation syndrome ?
    ### Response:
    Congenital central hypoventilation syndrome (CCHS) is a disorder that affects breathing. People with this disorder take shallow breaths (hypoventilate), especially during sleep, resulting in a shortage of oxygen and a buildup of carbon dioxide in the blood.
    