Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to nonsyndromic hearing loss ?
    ### Response:
    The causes of nonsyndromic hearing loss are complex. Researchers have identified more than 90 genes that, when altered, are associated with nonsyndromic hearing loss. Many of these genes are involved in the development and function of the inner ear. Mutations in these genes contribute to hearing loss by interfering with critical steps in processing sound.
    