Marfan syndrome is a genetic disorder affecting the body’s connective tissues, which help provide strength and flexibility to many parts of the body, including muscles, blood vessels, heart valves, and bones. The two main features of Marfan syndrome affect the heart and eyes. Specifically, the main artery carrying blood away from the heart (aorta) can widen over time (aortic aneurysm). This widening can cause the vessel to tear (aortic dissection). People with Marfan syndrome can also have dislocation of the lenses in their eyes (ectopia lentis), which can cause vision problems. Other features of Marfan syndrome include a long narrow face, a curved spine (scoliosis), a sunken or protruding chest, flat feet, flexible joints, and crowded teeth. People with Marfan syndrome may also have a total length of both arms (wingspan) that is longer than their height.
Marfan syndrome is caused by a mutation (change) in the FBN1 gene. This gene acts as an instruction for the body to make fibrillin-1, a protein that helps strengthen parts of the body while also controlling the release of growth factors into the blood. When a person has a mutation in the FBN1 gene, it causes parts of their body to be weaker than normal and also causes them to grow faster than they should. This combination is what causes the features of this condition. Marfan syndrome is inherited in an autosomal dominant way, which means a mutation in only one of the two copies of the gene a person has is enough to cause Marfan syndrome.
Marfan syndrome is suspected in a person with an enlarged aorta or dislocated lenses. Certain physical features can be seen on a physical exam, which can also suggest Marfan syndrome. The diagnosis is confirmed with genetic testing. Although there is no cure for Marfan syndrome, there are options to address many of the symptoms. In some cases, surgery may be needed. Support groups are available for support and more information.