Marfan Syndrome - Newcastle Hospitals NHS Foundation Trust

This information has been designed to answer some of the questions we are often asked about Marfan syndrome.

If you have any questions or if you would like to discuss anything in further detail, please feel free to ask your genetics doctor or nurse.

What is Marfan syndrome?

Dr Antoine Bernard Marfan described the first case of a new medical condition in Paris in 1896. Since then our understanding of Marfan syndrome has continued to expand, although we still have a lot to learn.

Marfan syndrome is a condition that affects the ‘connective tissue’ in different parts of the body.

Connective tissue is strong but flexible. It is made of many different chemicals, one of which is called ‘fibrillin’. People with Marfan syndrome have less fibrillin than usual and their connective tissue is weakened.

What causes Marfan syndrome?

The body makes its own fibrillin using a recipe called the fibrillin gene. If this gene contains a mistake the body is unable to make enough normal fibrillin, and this causes Marfan syndrome. In most cases, the mistake is like a simple spelling mistake in the gene which makes the recipe difficult to read.

How is Marfan syndrome inherited?

Everyone has two copies of the fibrillin gene – one comes from mum and the other from dad. Only one copy of the fibrillin gene needs to contain a mistake to cause Marfan syndrome. Such genetic faults are said to be ‘dominant’.

75% of people with Marfan syndrome have inherited the faulty fibrillin gene from an affected parent.

In 25% of cases, however, the gene fault occurs for the first time in the affected person. Although that person has no family history of Marfan syndrome, he/she could pass the faulty fibrillin gene on to his/her children.

Every time someone with Marfan syndrome has a child there is a 1 in 2 – or 50:50 – chance that the child will inherit the faulty copy of the fibrillin gene. This is called ‘dominant inheritance’ (see diagram).

A child who inherits a faulty copy of the fibrillin gene is likely to develop Marfan syndrome, although he/she may develop different problems to his/her parent.

Inheritance of Marfan syndrome

Each bar represents one copy of the fibrillin gene. Each parent has two copies. The affected parent has one normal copy (1), and one copy containing a fault (2).

There are 4 possible outcomes. Each child inherits one copy of the gene from each parent. On average, half of the children inherit the faulty fibrillin gene (2). These children are likely to develop features of Marfan syndrome as they grow older. This is known as dominant inheritance.

How is Marfan syndrome diagnosed?

At present, a doctor makes a diagnosis of Marfan syndrome by examining you, looking for evidence of weakened connective tissue in a different parts of the body. This can be more difficult in children because the signs of Marfan syndrome develop as children grow. For that reason, a child thought to have Marfan syndrome will be examined several times throughout childhood.

The doctor looks for connective tissue weakness in the skeleton, heart and eyes, since these areas contain a lot of fibrillin and they are most often affected in Marfan syndrome. This usually involves a full medical examination, an ultrasound heart scan called an ‘echo’, an eye examination and sometimes an X-ray of the pelvis.

Is there a gene test?

The simple answer is “not yet”. The fibrillin gene is very large and complex and this makes it difficult for us to read. So far we have only been able to work out the gene fault in a relatively small number of families. Each family seems to have their own, unique fault.

Sometimes the clinical geneticist may request a blood sample for genetic testing, although this is not routine. In the future, gene testing will be much easier, which should simplify the diagnosis of Marfan syndrome.

How Marfan syndrome might affect you

Marfan syndrome can affect many areas of the body, as explained below.

How does Marfan syndrome affect the skeleton?

Most people with Marfan syndrome are tall and thin with slender arms and legs, although this is not always the case. Fingers and toes are usually long and slender and flat feet are common. The front of the chest is often prominent or curved inwards.

A person with Marfan syndrome often has a very characteristic facial appearance. The roof of the mouth is usually high and arched like a church window, and the teeth may become crowded.

Joints may be more flexible than usual (‘double-jointed’) or stiff. The spine may develop an Sshaped curve known as a scoliosis. It is very important to detect this early as it may need correction with a brace, or sometimes surgery.

How does Marfan syndrome affect the heart?

The heart pumps blood into the main artery of the body known as the aorta. The wall of the aorta is usually strong and elastic, especially where the heart joins the aorta at the ‘aortic root’.

In Marfan syndrome the connective tissue in the aortic root is weakened, and the aortic root may stretch, or dilate. This happens in over 50% of adults with Marfan syndrome.

Stretching of the aortic root often starts to develop during childhood and, because it develops over time, the aortic root needs to be monitored on a regular basis using echo heart scans.

Any person with a stretched aortic root is referred to a cardiologist, who will prescribe medication that has been shown to slow the progression of aortic root stretching. The medication is known as a ‘beta (β) -blocker’. People with asthma may not tolerate beta (β) -blockers, so a different sort of medication may be prescribed.

In some people with Marfan syndrome the stretched aortic root develops a split called a dissection. This is a serious situation that requires surgical repair. Surgery can usually be planned, however, before a dissection occurs.

Another way in which the heart can be affected involves one of the heart valves known as the ‘mitral valve’. In Marfan syndrome the mitral valve can become ‘floppy’. This does not always cause symptoms.

Some people may develop breathlessness and an irregular pulse, and some people need to have their mitral valve repaired or replaced with an artificial valve. People with mitral valve problems are usually advised to take antibiotics when they have dental treatment or operations, to prevent infection of the valve.

How does Marfan syndrome affect the eyes?

People with Marfan syndrome are often short-sighted due to the shape of their eyes. The lens at the front of the eye dislocates in about 50% of people. This can usually be treated with glasses.

Some people may also experience detachment of the retina, which may need surgical treatment. It is important for people with Marfan syndrome to know that they may develop eye problems so that they can be treated quickly.

Can I take part in sports?

People with Marfan syndrome can take part in sport, but we would advise against contact sports like rugby and exercise that makes you strain a lot (like weight-lifting and squash) if your aortic root is dilated.

Is pregnancy safe?

Women with Marfan syndrome who have normal hearts usually tolerate pregnancy well. However, pregnancy can sometimes make the aortic root begin to stretch. Also, if a woman with Marfan syndrome already has a stretched aortic root this may increase during pregnancy.

For these reasons it is very important that you talk to your doctor if you are planning a family. Issues such as the method of delivery and pain relief need special attention and you should consider planning to deliver your baby in a central hospital such as the Royal Victoria Infirmary in Newcastle, or James Cook University Hospital in Middlesborough.

Does Marfan syndrome affect driving?

Your driving licence is not usually affected by a diagnosis of Marfan syndrome. However, you may be advised to notify the DVLA if you have severe visual impairment.

Can I still get insurance or a mortgage?

People with Marfan syndrome may experience difficulty with insurance or mortgage companies. If you need help and advice, please ask us and we can often support your application.

Where can I find more information?

The Internet is a good source of more detailed information about Marfan syndrome. Some of the information may not be accurate, or may be biased. We would recommend the following sites:

The Marfan Trust UK

This charity supports those with Marfan syndrome and their families; provides educational information to raise awareness of Marfan syndrome and undertakes medical research to enable better treatment for patients.

Your Genes Your Health

This website is hosted by the Dolan DNA Learning Center at Cold Spring Harbor in the US. It has an impressive interactive section on Marfan syndrome and also gives a detailed account of genetics and inheritance.

Genes Clinics

A detailed, up to date medical / technical account of Marfan syndrome written by Professor H Dietz, who has worked with people with Marfan syndrome for many years.