Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Proteus syndrome ?
    ### Response:
    What causes Proteus syndrome? Proteus syndrome is caused by mutations in the AKT1 gene. This genetic change is not inherited from a parent; it arises randomly in one cell during the early stages of development before birth. As cells continue to grow and divide, some cells will have the mutation and others will not.
    