marfan syndrome an autosomal dominant disorder of the connective tissues

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Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues.

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Page 1: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Marfan Syndrome

An Autosomal Dominant

Disorder of the Connective

Tissues.

Page 2: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Modes of Inheritance:

About 30% of cases occur when the abnormal gene arises in an egg or a sperm of an unaffected parent. Each child of a Marfan sufferer has a 50-50 chance of inheriting the syndrome

Most cases occur as a result of inheriting the gene from an affected parent.

Page 3: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Pedrigree of Marfan Syndrome

I

II

III

IV

1.1

2.5

1.2

2.1 2.42.32.2

3.23.1

2.6

3.43.3

4.1RED = affected

GREEN = unaffected

Page 4: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Symptoms:

Irregular heart rhythms Leakage of the mitral valve Curvature of the spine (scoliosis) Pectus deformity Disproportionate growth (usually tall) Myopic (near-sighted) Dislocation of ocular lens

Page 5: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Chromosomal Location:

A single abnormal gene located on chromosome 15 and containing the coding for fibrilin, a connective tissue protein, is responsible for the syndrome.

Page 6: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Frequency of Occurrence:

This condition affects both men and women of any race or ethnic group.

At least 200,000 individuals in the United States suffer from Marfan Syndrome.

Page 7: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Biochemistry of Marfan:

http://www.ncbi.nlm.nih.gov/disease/marfan

Page 8: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Diagnosing Marfan: Marfan is difficult to diagnose because there

is not a specific test for the disorder. However, certain tests are useful in diagnosing the ailment:– Echocardiogram (sound wave picture of the

heart)– X-rays – Slit-lamp eye examination– Skeletal examination – Complete family history

Page 9: Marfan Syndrome An Autosomal Dominant Disorder of the Connective Tissues

Treating Marfan: Every person with Marfan Syndrome should have regular

echocardiograms to check the size and function of the heart and aorta.

A careful eye examination using a slit lamp to detect lens dislocation is recommended.

Glasses may be prescribed to correct visual defects. Careful monitoring of the skeleton, particularly during childhood and

adolescence, is necessary. Beta blocker medications may be prescribed to lower blood pressure,

to reduce stress to the aorta. Antibiotics may be prescribed prior to dental procedures to reduce

the risk of infection in people with mitral valve prolapse. Adapted lifestyles, such as avoiding contact sports or strenuous

exercise, to reduce the risk of injury to the aorta.