We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
Abbott Diagnostics

Download Mobile App


ATTENTION: Due to the COVID-19 PANDEMIC, many events are being rescheduled for a later date, converted into virtual venues, or altogether cancelled. Please check with the event organizer or website prior to planning for any forthcoming event.
27 Oct 2020 - 31 Oct 2020
Virtual Venue
28 Oct 2020 - 30 Oct 2020
Virtual Venue

Large Genome-Wide Association Study Identifies Novel Abdominal Aortic Aneurysm Risk Loci

By LabMedica International staff writers
Posted on 05 Oct 2020
Print article
Image: Illustration of the heart with magnification of the artery (Photo courtesy of American Heart Association)
Image: Illustration of the heart with magnification of the artery (Photo courtesy of American Heart Association)
A recent report identified novel genetic associations for abdominal aortic aneurysm (AAA) with therapeutic implications and identified a subset of the population at significantly increased genetic risk of AAA that was independent of family history.

AAA is a localized enlargement of the abdominal aorta such that the diameter is greater than three centimeters or more than 50% larger than normal. They usually cause no symptoms, except during rupture. Rupture may result in pain in the abdomen or back, low blood pressure, or loss of consciousness, and often results in death. AAAs occur most commonly in men over 50 years old, and among those with a family history. Additional risk factors include smoking, high blood pressure, and other heart or blood vessel diseases. AAAs are the most common form of aortic aneurysm. In the United States, screening with abdominal ultrasound is recommended for males between 65 and 75 years of age with a history of smoking. The genetic determinants of AAA remain incompletely defined. In total, 10 previously identified risk loci explain only a small fraction of the inheritance of AAA.

Investigators at Stanford University (Palo Alto, CA, USA) and a large number of collaborators from other institutions performed a genome-wide association study (GWAS) on samples obtained from the Million Veteran Program. This program, which was initiated in 2011 and is now one of the world's largest genetic biobanks, was designed to promote the study of how genes affect the health of United States military veterans.

For the current study, the investigators performed a GWAS on nearly 18 million DNA sequence variants with AAA (7,642 cases and 172,172 controls) in veterans of European ancestry with independent replication in up to 4,972 cases and 99,858 controls. They then used Mendelian randomization to examine the causal effects of blood pressure on AAA. In addition, they examined the association of AAA risk variants with aneurysms in the lower extremity, cerebral, and iliac arterial beds, and derived a genome-wide polygenic risk score (PRS) to identify a subset of the population at greater risk for the disease.

Results revealed 14 novel genetic loci, bringing the total number of known significant AAA loci to 24. A genetic-linked increase of 10 millimeters of mercury (Hg) in diastolic blood pressure increased the risk of developing abdominal aortic aneurysm. Analysis showed further that 19 of the 24 risk loci for AAA were associated with aneurysms in other parts of the body. A 29-variant PRS was strongly associated with AAA, independent of family history and smoking risk factors. Using this PRS, the investigators identified a subset of the population with AAA prevalence greater than that observed in screening trials performed according to current guidelines.

"This study has doubled the number of genetic associations with abdominal aortic aneurysm, adding greatly to our understanding of the disease mechanisms," said senior author Dr. Philip S. Tsao, professor of cardiovascular medicine at Stanford University. "We were surprised that diastolic blood pressure, as opposed to systolic blood pressure, is likely of greater significance in the development of abdominal aortic aneurysm. This new information can enhance screening protocols and help identify individuals at risk for abdominal aortic aneurysm."

The AAA study was published in the September 28, 2020, online edition of the journal Circulation.

Related Links:
Stanford University

Print article
BIOHIT  Healthcare OY


Industry News

view channel
Image: Mindray Hematology Solution Helps High-Volume Lab Run 2,820,000 CBC Tests Annually (Photo courtesy of Mindray)

Mindray Hematology Solution Helps High-Volume Lab Run 2,820,000 CBC Tests Annually

High-volume laboratories face several challenges, including high instrument failure rate, errors due to several manual steps, low efficiency and long TAT, and heavier workload for the lab staff.... Read more
Copyright © 2000-2020 Globetech Media. All rights reserved.