Fibrillin 1
What is Fibrillin?
Marfan syndrome is caused by changes in fibrillin genes. Fibrillin is a glycoprotein, which is essential for the formation of elastic fibers or microfibrils that provide strength and flexibility to connective tissue. Connective tissue holds the body together and helps control the growth and repair of tissues and organs. Fibrillin normally is abundant in the connective tissue found in the aorta, in the ligaments that hold the eye's lenses in place, in the bones and the lungs.How is Fibrillin related to Marfan syndrome?
Marfan syndrome is caused by changes (mutations) in one member of the pair of fibrillin genes. As a result, the body produces fibrillin that does not work and connective tissue that is not as strong as it should be. The growth and development of the body are affected, particularly in the connective tissues of the aorta, eye and skin. It causes overgrowth of the long bones of the body, resulting in tall height, long arms and legs, and a weakened structural support in blood vessels, heart valves, cartilage and ligaments.
How does the body produce Fibrillin?
FBN1 are the genes responsible for the production of fibrillin in the body. These genes are located on chromosome 15, one of the 23 pairs of human chromosomes. Fibrillin binds to itself and other proteins and molecules to form the microfibrils that become part of the connective tissue.
Who is at risk to inherit the mutated Fibrillin gene?
The mutated fibrillin gene usually is inherited from one parent who has Marfan syndrome. The mutation is a "dominant genetic trait. This means that each child of a parent with Marfan syndrome has a 50 percent chance of inheriting the mutation, and a 50 percent chance of not inheriting it. Only those children who inherit the mutation will develop the signs and symptoms of Marfan syndrome. About 25 percent of Marfan syndrome cases are sporadic. This means that they are caused by a new mutation that occurred by chance in one of the fibrillin genes of an unaffected parent.
How do I find out if I have the FBN1 Gene?
Testing or gene coding for FBN1 is normally conducted through DNA analysis in a laboratory setting. In general, these tests may detect most but not all of the mutations in the FBN1 Gene. Persons interested in genetic testing should consult with their physician or genetic counselor at the Stanford Hospital & Clinics.