Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to megalencephaly-capillary malformation syndrome ?
    ### Response:
    MCAP is caused by mutations in the PIK3CA gene, which provides instructions for making the p110 alpha (p110) protein. This protein is one piece (subunit) of an enzyme called phosphatidylinositol 3-kinase (PI3K), which plays a role in chemical signaling within cells.
    