Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to retinitis pigmentosa ?
    ### Response:
    Mutations in more than 60 genes are known to cause nonsyndromic retinitis pigmentosa. More than 20 of these genes are associated with the autosomal dominant form of the disorder. Mutations in the RHO gene are the most common cause of autosomal dominant retinitis pigmentosa, accounting for 20 to 30 percent of all cases.
    