The goal of this study is to identify genes that cause abdominal aortic aneurysms (AAA) by carrying out genomic analyses, including next generation DNA sequence analysis, of families with multiple affected AAA cases. AAA is the thirteenth leading cause of death in the US and a major cause of death in the elderly. There is a pressing need for research that leads to better means to diagnose and treat AAA. Identifying functional genetic variants associated with AAA provides the best way to gain insight into the underlying disease mechanisms as a means to develop new diagnostic tests and medical therapies. This will be done by contacting the participants that rolled in the original AAA study(study #2006-0211) and have a confirmed AAA. We will contact these patients and ask them for contact information on their family members as well as questions regarding family history of AAA. If these participants provide us with information to contact their family members, we will then contact the family members and enroll them into this study(2011-0207). We will collect blood or saliva samples to test for genetic markers. This study is linked to the original AAA study(2006-0211) so that we can study family history and genetics of the family members of the confirmed AAA cases.