Below is an instruction from Human. Write a response.
    ### Instruction:
    Who is at risk for Marfan Syndrome? ?
    ### Response:
    People at highest risk for Marfan syndrome are those who have a family history of the condition. If you have Marfan syndrome, you have a 50 percent chance of passing the altered gene to each of your children.
                
Marfan syndrome affects about 1 out of every 5,000 people in the United States.
    