Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to Nager syndrome ?
    ### Response:
    The cause of Nager syndrome is unknown. Although the specific genes involved have not been identified, researchers believe that this condition is caused by changes in a particular region of chromosome 9 in some families.  Nager syndrome disrupts the development of structures called the first and second pharyngeal arches.
    