Epidemiology
Marfan syndrome affects males and females equally, and the mutation shows no ethnic or geographical bias. Estimates indicate about one in 3,000 to 5,000 individuals have Marfan syndrome. Each parent with the condition has a 50% risk of passing the genetic defect on to any child due to its autosomal dominant nature. Most individuals with Marfan syndrome have another affected family member — approximately 15–30% of all cases are due to de novo genetic mutations—such spontaneous mutations occur in about one in 20,000 births. Marfan syndrome is also an example of dominant negative mutation and haploinsufficiency. It is associated with variable expressivity; incomplete penetrance has not been definitively documented.
Read more about this topic: Marfan Syndrome