FBN1 and Aortic root aneurysm: Marfan syndrome is a human autosomal dominant disease caused by loss‐of‐function variants in FBN1. The clinical features of Marfan syndrome include aortic root aneurysm/dissection, ectopia lentis, and findings in other organ systems such as skeleton, skin, and lungs (Loeys et al., 2010).