Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to juvenile polyposis syndrome ?
    ### Response:
    Mutations in the BMPR1A and SMAD4 genes cause juvenile polyposis syndrome. These genes provide instructions for making proteins that are involved in transmitting chemical signals from the cell membrane to the nucleus. This type of signaling pathway allows the environment outside the cell to affect how the cell produces other proteins.
    