Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to hypercholesterolemia ?
    ### Response:
    Mutations in the APOB, LDLR, LDLRAP1, and PCSK9 genes cause hypercholesterolemia.  High blood cholesterol levels typically result from a combination of genetic and environmental risk factors. Lifestyle choices including diet, exercise, and tobacco smoking strongly influence the amount of cholesterol in the blood.
    