Marfan syndrome is a disorder of the connective tissue that affects the skeleton, eyes, cardiovascular system, and other areas. It is caused by mutations in the FBN1 gene, which provides instructions for making a protein called fibrillin-1 that is important for connective tissue strength and flexibility. Marfan syndrome is inherited in an autosomal dominant pattern, so if one parent has it there is a 50% chance their child will have it as well. While there is no cure, treatment focuses on managing symptoms and complications through monitoring by specialists and may include surgeries or medicines.