Marfan syndrome is an inherited genetic disorder. It can affect many parts of the body, including the skeleton, eyes, heart and blood vessels. A genetic disorder is caused by one or more changed genes.
Our bodies are made up of millions of cells. Each cell contains a complete set of genes.
We have thousands of genes. We each inherit two copies of most genes, one copy from our mother and one copy from our father. Genes act like a set of instructions, controlling our growth and how our bodies work. Any alteration in these instructions is called a mutation (or change). Mutations (or changes) can stop a gene from working properly. A mutation (change) in a gene can cause a genetic disorder. Genes are responsible for many of our characteristics, such as our eye colour, blood type or height.
Everyone with Marfan syndrome has a change (mutation) in a gene which makes a substance called fibrillin. Fibrillin is an important part of connective tissue. Connective tissue helps to provide a framework for body growth and development. Problems with connective tissue can affect many parts of the body.
A syndrome is a pattern of features occurring together. The features of Marfan syndrome can vary greatly from one person to another, even within the same family. The majority of people with Marfan syndrome do not have all the features and complications associated with the syndrome. The most common features of Marfan syndrome are:

The most serious problems associated with Marfan syndrome involve the heart and blood vessels. The aorta is a very large blood vessel that carries blood from the heart to the rest of the body. In people with Marfan syndrome, the wall of the aorta can become weakened and stretched (aortic dilatation). If left untreated, aortic dilatation can cause the wall of the aorta to tear or rupture causing very serious heart problems.
People with Marfan syndrome should be monitored regularly to help prevent this.
Some affected people have changes in the heart structure, which can cause problems with the normal working and rhythm of the heart. This can cause fatigue and shortness of breath. People with these structural changes in the heart are also susceptible to the effects of infections on the heart. These people may be advised to take antibiotics in some situations, for instance before they have dental work done.
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Many people with Marfan syndrome are very tall, or at least taller than unaffected family members. Marfan syndrome affects the long bones of the skeleton, so that affected people may have particularly long arms, legs, fingers and toes. A person with
Marfan syndrome typically has a long, narrow face. The roof of the mouth may be arched, which can make the teeth crowded. Other problems with the skeleton can include curvature of the spine (scoliosis) and an abnormally shaped breast-bone or sternum.
The lens is a very important part of the eye that acts in a similar way to a lens in a camera. Any problems with the lens can affect vision. The lens is held in place by connective tissue. In people with Marfan syndrome one or both of the lenses may slip out of place. This is called dislocation of the lens. Many people with Marfan syndrome are short-sighted myopic and they may need to wear glasses.
In general, Marfan syndrome is diagnosed after a careful physical examination by a specialist team of doctors. Certain tests, such as an echocardiogram (a way to examine the heart using sound) and a careful eye examination may be done if the doctor thinks a diagnosis of Marfan syndrome is likely. Marfan syndrome can be difficult to diagnose, especially in children. The condition progresses with age, so that a person may not develop problems until later in life.
There is no cure for Marfan syndrome. However, monitoring and treatment options can minimise and sometimes prevent complications.

 Every person with Marfan syndrome should have regular echocardiograms to check the heart and aorta. Medication may be used to lower blood pressure and reduce stress on the aorta.
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 Children, in particular, should be monitored regularly to check for problems with the skeleton, particularly the spine. Treatment can be helpful if problems are detected early. Children with Marfan syndrome should also be seen by a specialist dentist
(orthodontist) to check for problems with overcrowded teeth.
 A regular check up by an eye specialist is advised to check for complications such as dislocation of the lens. Most eye problems can be corrected by glasses or contact lenses, but some may need surgery.
The nature of the complications associated with Marfan syndrome means that lifestyle changes may be advisable. For instance, it may be necessary to avoid very strenuous exercise to reduce the risk of problems with heart and blood vessels. It may be advisable to avoid contact sports, to prevent injuries to the eyes.
Any pregnant woman’s heart is under more strain than normal, as it has to pump a larger amount of blood. Women with Marfan syndrome are at risk of having the heart problems mentioned, so they should be monitored by a cardiologist, a specialist heart doctor, throughout pregnancy.
Everybody has two copies of the fibrillin gene. People with Marfan syndrome have two copies of the gene but one of them has a mutation (change). The normal copy cannot compensate for the effects of the changed copy of the gene. When people who have a fibrillin gene with a mutation (change) have children, they can pass on either their normal copy of the fibrillin gene, or the copy with the mutation (change). This means there is a 1 in
2, or 50% chance of their child inheriting the gene with the change (mutation). There is also a 1 in 2, or 50% chance of their child inheriting the normal copy of the gene.
In about a quarter (25%) of cases, a person with Marfan syndrome is the only affected person in the family. This can happen when the change (mutation) in the gene arises only in the egg or sperm of a parent, but is not present in any other type of cell. When this happens the parent is not affected, but the parent can pass on the gene with the mutation
(change) to any children. In this case, the parents have a very low chance of having another child with the condition. However the affected child who inherited the gene with the mutation (change) can pass it on to the next generation.

Marfan syndrome is caused by a mutation (change) in the fibrillin gene. There is a genetic test to find out whether someone has the gene change (mutation) or not. The diagnosis of
Marfan syndrome can also be made by physical examination by a specialist doctor. In some families, it may be possible to test a baby during the mother’s pregnancy. This is called prenatal diagnosis.
This is only a brief guide to Marfan syndrome and only the most common features of the disorder have been covered here. More information can be obtained from your local regional genetics centre or from these addresses:
Rochester House
5 Aldershot Rd
Fleet
Hampshire
GU51 3NG
Tel: 01252 810472 Fax : 01252 810473 Web: www.marfan.org.uk
Unit 4D,
Leroy House,
436 Essex Rd.,
London, N1 3QP
Telephone: 020 7704 3141 Email : mail@gig.org.uk
Web : www.gig.org.uk
209-211 City Rd.,
London,
EC1V 1JN
Telephone: 020 7608 8700
FAX: 020 7608 8701
Helpline 0808 808 3555 or Textphone 0808 808 3556
(Freephone for parents and families, 10am-4pm, Mon-Fri) e-mail: info@cafamily.org.uk
Web: www.cafamily.org.uk
This edition prepared in July 2005 Ref: 15
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This glossary is intended only to explain terms used in the information: Marfan syndrome.
Words shown in bold are defined elsewhere in the glossary.
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Medicines which treat bacterial infections.
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A very large blood vessel that carries blood from the heart to the rest of the body.
Weakening and stretching of the aorta .
A doctor who specialises in conditions which affect the heart.
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The human body is made up of millions of cells, which are like building blocks. There are many specialised types of cells. These include skin cells, brain cells, and blood cells.
Cells in different parts of the body look different and do different things. Every cell (except for eggs in women and sperm in men) contains all the body’s genes.
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A general term, this includes many types of specialised cells which join and support the parts of the body.
See scoliosis.
of the lens of the eye. This is a shifting of the lens from its normal position.
A special way to examine the heart. It uses sound, from a device outside the chest, to give a picture of how the heart is working.
The mother’s contribution to the cell which will grow to make a new baby. The egg contains 23 chromosomes ; one from each pair in the mother. A sperm also contains 23 chromosomes one from each of the father’s pairs. The egg joins with a sperm to make a complete cell.
A baby develops from this first cell.
gene . The gene which is changed in Marfan syndrome . The gene makes fibrillin, which is important to the normal working of connective tissue in the body. When the gene has a mutation (change) as in Marfan syndrome , the fibrillin is changed and the connective tissue does not work normally.
Information needed for the body to work, stored in a chemical form. Changes or mutations in genes alter the information and this can change how the body works. Most genes are in pairs: one from the mother, one from the father. (As an analogy: a gene is like a story in a book, a change or mutation in a gene is like a missing or extra letter in a word in the story).
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Caused by genes , concerning genes.
Part of the eye which allows us to focus on things we see.

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A change in a gene . Some mutations are not harmful. Sometimes when a gene is changed, its information is altered so it does not work properly. (As an analogy: a change or mutation in a gene is like a missing or extra letter in a word in a story).
Short-sighted. Has difficulty seeing things in the distance.
A specialist dentist who can check for problems with overcrowded teeth, and who can help with these problems.
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Test during a pregnancy for the presence or absence of a genetic disorder in the baby.
( also known as curvature of the spine).
A sideways curve in the spine.
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The father’s contribution to the cell which will grow to form a new baby. Each sperm contains 23 chromosomes ; one from each pair in the father. An egg contains one chromosome from each of the mother’s 23 pairs. The sperm joins with an egg to make a complete cell.
A baby develops from this first cell.
The backbone. The series of bones in the middle of the back
The breast bone; the bone at the centre of the front of the chest.
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A group of features which occur together in affected people. Affected people share some or all of the features of the syndrome .
This glossary is intended only for use by patients and families, with the genetic information to which it refers.
This edition prepared in July 2005 Ref Glossary 15
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