Marfan syndrome is not very common 1 in 5,000 people suffer from it. Marfan syndrome is a heritable condition that affects the connective tissue. The primary purpose of connective tissue is to hold the body together and provide a framework for growth and development. In Marfan syndrome, the connective tissue is defective and does not act as it should. Because connective tissue is found throughout the body, Marfan syndrome can affect many body systems, including the skeleton, eyes, heart and blood vessels, nervous system, skin, and lungs. Marfan syndrome affects men, women, and children. Marfan syndrome affects different people in different ways. Some people have only mild symptoms, while others are more severely affected. In most cases, the symptoms progress as the person ages. People with Marfan syndrome are typically very tall, slender, and loose-jointed because Marfan syndrome affects the long bones of the skeleton, a person's arms, legs, fingers, and toes may be disproportionately long in relation to the rest of the body. More than half of all people with Marfan syndrome experience dislocation of one or both lenses of the eye. The brain and spinal cord are surrounded by fluid contained by a membrane called the Dura, which is composed of connective tissue. As someone with Marfan syndrome gets older, the dura often weakens and stretches, then begins to weigh on the vertebrae in the lower spine and wear away the bone surrounding the spinal cord. Many people with Marfan syndrome develop stretch marks on their skin, even without any weight change. These stretch marks can occur at any age and pose no health risk. The FBN1 gene is affected from Marfan syndrome. Mutations in the FBN1 gene cause Marfan syndrome. The FBN1 gene provides instructions for making a protein called fibrillin-1. Fibrillin-1 attaches (binds) to other