Marfan syndrome

Marfan syndrome is an inherited disease of connective tissue, the material the body uses to hold itself together and anchor its parts on the inside. It is among the most common of these disorders and affects an estimated 1 in every 3000 to 5000 people. It is inherited in an autosomal dominant pattern, which means one altered copy of the gene is enough to cause it.

The gene that fails is called FBN1 and sits on chromosome 15. Its job is to make fibrillin, a connective tissue protein. Fibrillin-1 is the main component of the elastic fibers, the ones that give tissue its ability to stretch and spring back. The faulty fibrillin is not in one organ: it is in the elastic material of every organ.

That is why Marfan syndrome shows up in very different places at once: in the eyes, in the heart and blood vessels, and in the bones and muscles. Fingers grow long and slender, which is called arachnodactyly, and the lens of the eye can slip out of place, which is called lens dislocation. The complications that shorten life the most are those of the aorta, the main artery leaving the heart.