The dramatic reductions in DNA sequencing costs allow us to delve deeper into the genomic alterations that increase susceptibility to many polygenic cardiovascular diseases. One such condition is an abnormal proximal aorta. Until recently, many believed that dilated, distorted or dissected proximal aortas might represent a forme fruste of Marfan syndrome or a continuum of aortopathy. Although an FBN-1 mutation does not guarantee the diagnosis of Marfan syndrome it is clear however that FBN-1 mutations independently confer additional risk for many of the cardiovascular complications classically associated with the disease. Furthermore, treatment with an angiotensin receptor blocker has proven effective in reducing rates of thoracic aortic root dilatation in preliminary studies of Marfan syndrome patients. Awareness of an FBN-1 mutation then highlights the need for increased vigilance for the associated cardiovascular phenotypes. Knowledge of an FBN-1 gene mutation may allow actionable interventions earlier in the natural history of the condition.