Aortic Aneurysm, Familial Thoracic 12, is also known as aat12. An important gene associated with Aortic Aneurysm, Familial Thoracic 12 is THSD4 (Thrombospondin Type 1 Domain Containing 4). Affiliated tissues include smooth muscle, and related phenotypes are aortic root aneurysm and ascending aortic dissection