MFS is an inherited disorder that affects 1:5000 of the population (i.e., 6000 people) in Canada alone. In MFS, mutations in the FBN1 gene lead to production of abnormal fibrillin 1 and to connective tissue abnormalities that impair skeletal, ocular, pulmonary and, most importantly, cardiovascular systems. Cardiovascular complications are also related to endothelial dysfunction, which has widespread implications for the health of large and muscular blood vessels and has effects on blood pressure, thrombosis, cholesterol levels and general vascular homeostasis. In MFS, progressive dilation, dissection and rupture of the aortic root may occur. This dilation is not solely due to the primary abnormality in collagen caused by the abnormal fibrillin protein. It remains unclear what the vascular mechanisms are that cause dilation of the aortic root. Eventual aortic rupture is a major cause of sudden death in MFS. If untreated, MFS significantly shortens the lifespan of affected individuals: half will succumb in their late 20s or early 30s, usually of aortic rupture. As such, it is crucial to develop effective treatments for cardiovascular disease in MFS and to improve our ability to detect critical changes in blood vessel (aortic) structure and function.