FBN1 and hereditary disorder of connective tissue: Marfan syndrome (MFS) is mainly caused by the fibrillin‐1 (FBN1) gene mutation and is a hereditary disorder of connective tissue with effects on multiple systems including cardiovascular, skeletal and ocular.1 FBN1 encodes the extracellular matrix protein FBN1 and is involved in the formation of complex extracellular structures in the arteries.