FBN1 and Marfan syndrome: However, FBN1 variants may also be present in individuals with incomplete Ghent criteria (without complete phenotype or with isolated findings) [13, 14]; i.e. inherited forms affecting only one of the systems involved in MFS, like isolated ectopia lentis, isolated ascending aortic aneurysm and/or dissection (AAD) or skeletal manifestations [14–16].