Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to congenital central hypoventilation syndrome ?
    ### Response:
    Mutations in the PHOX2B gene cause CCHS. The PHOX2B gene provides instructions for making a protein that acts early in development to help promote the formation of nerve cells (neurons) and regulate the process by which the neurons mature to carry out specific functions (differentiation).
    