Loeys-Dietz Syndrome 3, also known as aneurysm-osteoarthritis syndrome, is related to supravalvular aortic stenosis and loeys-dietz syndrome 1. An important gene associated with Loeys-Dietz Syndrome 3 is SMAD3 (SMAD Family Member 3), and among its related pathways/superpathways are ERK Signaling and Signal Transduction. Affiliated tissues include heart and bone, and related phenotypes are pes planus and dilatation of the sinus of valsalva