What major sign is associated with Marfan syndrome?

Marfan syndrome is a connective tissue disorder caused by mutations in the FBN1 gene, which encodes the protein fibrillin-1. One of the hallmark features of Marfan syndrome is lens dislocation, specifically displacement of the lens from its normal position within the eye. This occurs because the abnormal connective tissue affects the zonules that hold the lens in place, leading to a higher risk of lens dislocation. Individuals with Marfan syndrome may experience a variety of ocular issues, but the displacement of the lens (ectopia lentis) is particularly characteristic of the syndrome and can be an important diagnostic criterion.

While scoliosis, flat feet, and short stature can occur in individuals with Marfan syndrome, they are not defining features of the condition. Scoliosis can be seen in many other conditions and does not specifically indicate Marfan syndrome. Similarly, while flat feet and short stature might be associated with various connective tissue disorders or genetic syndromes, lens dislocation is uniquely significant in the context of Marfan syndrome, making it the major sign linked with this disorder.