Pathophysiology and J apanese clinical characteristics in M arfan syndrome

Marfan syndrome is an autosomal dominant heritable disorder of the connective tissue, caused by mutations of the gene FBN1 , which encodes fibrillin‐1, a major component of the microfibrils of the extracellular matrix. Fibrillin‐1 interacts with transforming growth factor‐β ( TGF‐ β), and dysregulated TGF‐ β signaling plays a major role in the development of connective tissue disease and familial aortic aneurysm and dissection, including M arfan syndrome. Losartan, an angiotensin II blocker, has the potential to reduce TGF‐ β signaling and is expected to be an additional therapeutic option. Clinical diagnosis is made using the G hent nosology, which requires comprehensive patient assessment and has been proven to work well, but evaluation of some of the diagnostic criteria by a single physician is difficult and time‐consuming. A M arfan clinic was established at the U niversity of T okyo H ospital in 2005, together with cardiologists, cardiac surgeons, pediatricians, orthopedists, and ophthalmologists in one place, for the purpose of speedy and accurate evaluation and diagnosis of M arfan syndrome. In this review, we discuss the recent progress in diagnosis and treatment of M arfan syndrome, and the characteristics of Japanese patients with M arfan syndrome.