Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Proteus syndrome ?
    ### Response:
    Proteus syndrome is characterized by excessive growth of a part or portion of the body. The overgrowth can cause differences in appearance and with time, an increased risk for blood clots and tumors. It is caused by a change (mutation) in the AKT1 gene. It is not inherited, but occurs as a random mutation in a body cell in a developing baby (fetus) early in pregnancy.
    