While a majority of Marfan syndrome can be attributed to mutations in the fibrillin-1 gene, our results documenting Lrp1 inactivation causes similar pathology including the progression to cardiomyopathy suggest that Lrp1 dysfunction may account for at least some of the Marfan-like syndrome unrelated to fibrillin mutations [42]. Here, FBN1 is linked to cardiomyopathy.