Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Myhre syndrome ?
    ### Response:
    What causes Myhre syndrome? Myhre syndrome is caused by mutations in the SMAD4 gene. This gene provides instructions for making a protein involved in transmitting chemical signals from the cell surface to the nucleus. This signaling pathway, called the transforming growth factor beta (TGF-) pathway, allows the environment outside the cell to affect how the cell produces other proteins.
    