Marfan syndrome is a genetic condition caused by a mutation, or change, in one of your genes, called the fibrillin-1 (FBN1) gene. The FBN1 gene makes fibrillin-1, which is a protein that forms elastic fibers within connective tissue. Fibrillin-1 also affects levels of another protein that helps control how you grow.
Most people who have Marfan syndrome inherit it from their parents. Sometimes, the mutation that causes Marfan syndrome is not passed down from a parent but happens by chance while the unborn baby is developing in the womb.
When a parent has Marfan syndrome, there is a 50 percent chance that their child will have it. Every person inherits two FBN1 genes, one gene from each parent. Children who inherit an FBN1 gene with a mutation from one parent will have Marfan syndrome even if they have a normal FBN1 gene from the other parent.
What does fibrillin-1 do?
Fibrillin-1 makes elastic fibers that provide strength and flexibility so your skin, blood vessels, and ligaments can stretch and bounce back. These fibers also attach to another protein called transforming growth factor-beta (TGF-beta). TGF-beta helps control how the body grows and develops. If fibrillin-1 does not work properly, there is too much TGF-beta, which causes your bones to grow more than usual. The signs and symptoms of Marfan syndrome are caused by not having enough elastic fibers and having too much active TGF-beta in your body.
Marfan syndrome affects people of all races and ethnicities and men and women equally.
Your risk for Marfan syndrome is higher if one or both parents have the condition. Learn how Marfan syndrome is inherited and the risk of passing the condition on to a child in our Causes section.
To screen for Marfan syndrome, your doctor may do a physical exam, including a check for certain body features common to the condition, and may ask about your symptoms. Depending on your age, your doctor may suggest a genetic test.
Siblings, parents, or children of a person who has Marfan syndrome—also known as first-degree relatives—may want to have genetic testing for the condition even if they do not have symptoms. Other relatives, such as first cousins and half-siblings, may be tested if they have symptoms or if the family is concerned that the person may have Marfan syndrome. Learn more in Diagnosis.
There is no way to prevent Marfan syndrome. Couples who are planning to have children and know that they are at risk of having a child with Marfan syndrome may want to meet with a genetic counselor. A genetic counselor can answer questions about the risk and explain the choices that are available.
Signs and symptoms of Marfan syndrome depend on which parts of the body are affected and the severity of the condition. Some people have few or no signs or symptoms, while others experience severe symptoms or life-threatening complications.
Signs and symptoms of Marfan syndrome may include:
Marfan syndrome most commonly affects the connective tissue of the heart and blood vessels, eyes, bones, lungs, and spinal cord. However, the condition can affect many parts of the body.
The most serious complications are in the heart and aorta and may include:
Other complications may include:
Your doctor will diagnose Marfan syndrome based on your medical and family history, a physical exam, and test results. No single test can diagnose Marfan syndrome, so doctors use a set of guidelines called the Ghent criteria to help. The Ghent criteria include whether the diameter of your aorta is larger than normal, whether your eye lens has ever moved out of place, whether you have certain physical signs of Marfan syndrome, and sometimes genetic testing.
If you are diagnosed with Marfan syndrome, all of your first-degree relatives, including parents, siblings, and children, should be screened for the disorder, even if they do not have signs and symptoms.
Your doctor will ask about signs and symptoms, your medical history, and your family’s medical history. For example, your doctor may ask whether any of your family members have Marfan syndrome, have had an aortic aneurysm, or have had heart problems.
During the physical exam, your doctor will look for signs of Marfan syndrome. For example, he or she may check the curve of your spine and the shape of your feet.
Your doctor may recommend one or more of the following tests to help diagnose Marfan syndrome:
While Marfan syndrome has no cure, treatments can help delay or prevent complications, especially when started early. The type of treatment you receive will depend on what parts of your body are affected and the severity of your condition. You may have a team of doctors and specialists to coordinate your care.
In addition to your primary care doctor, your healthcare team may include:
Your doctor may recommend blood pressure medicines to relieve any strain on or bulging of the aorta. These medicines help your heart beat slower and with less force.
If your aorta is larger than normal, your doctor may recommend surgery to repair or replace part of the aorta to prevent it from rupturing or tearing open. If you have an aortic dissection or rupture, you will need emergency surgery to repair the aorta.
Your aortic valve may also be replaced with a mechanical or biological valve made from animal tissue. The valve may be replaced during the open surgery to repair the aneurysm.
If you have mitral regurgitation—where your blood flows backward into your left atrium—your doctor may recommend surgery to repair or replace your mitral valve.
Your doctor may also recommend surgery for one of the following reasons:
If you have been diagnosed with Marfan syndrome, it is important to follow your treatment plan, make healthy lifestyle changes, and get mental health support. Learn how to prevent or reduce complications in the future. If you are thinking about becoming pregnant, discuss the possible risks with your doctor.
How often you need to see your doctor for follow-up care will depend on your treatment and symptoms.
Return to Treatment to review possible treatment options for Marfan syndrome.
To monitor your condition, your doctor may recommend the following tests:
People who have Marfan syndrome may need more than one heart or blood vessel surgery over time. After surgery, you may need medicines and regular monitoring. Follow all medical instructions given by your doctor. Recovery after open surgery may take months.
To help prevent complications from Marfan syndrome, your doctor may recommend you avoid the following:
Living with Marfan syndrome may cause fear, anxiety, depression, and stress. Talk about how you feel with your healthcare team. Your doctor may recommend:
If you have Marfan syndrome, you are at risk for a life-threatening aortic dissection. If your aorta is weaker or larger than normal, it is important to know the signs and symptoms of a dissection or rupture, which may include:
If you have symptoms of aortic dissection or rupture, call 9-1-1.
To prepare for an emergency:
Many women who have Marfan syndrome have safe and healthy pregnancies and deliveries. However, there are some added risks during pregnancy and delivery. The most serious risk is aortic dissection due to extra strain on the heart. If you have Marfan syndrome and have already experienced aortic dissection, it is not safe for you to become pregnant.
If you are thinking about getting pregnant, talk with an obstetrician, a doctor who cares for pregnant women, who is familiar with your condition and has experience with high-risk pregnancies. Your doctor might recommend that you have surgery to fix your aorta before you try to get pregnant. Your doctor will also make sure that your medicines are safe to take during pregnancy.
Learn about the following ways the NHLBI continues to translate current research into improved health for people with Marfan syndrome. Research on this topic is part of the NHLBI’s broader commitment to advancing heart and vascular disease scientific discovery.
Learn about some of the pioneering research contributions we have made over the years that have improved clinical care.
In support of our mission, we are committed to advancing research into vascular and genetic diseases, including Marfan syndrome, in part through the following ways.
Learn about exciting research areas the NHLBI is exploring that involve Marfan syndrome.
We lead or sponsor many studies aimed at preventing, diagnosing, and treating heart, lung, blood, and sleep disorders. See if you or someone you know is eligible to participate in our clinical trials.
After reading our Marfan Syndrome Health Topic, you may be interested in additional information found in the following resources.