Navigation Links
Johns Hopkins researchers identify new genetic risk factor for sudden cardiac death
Date:7/12/2011

In a large and comprehensive investigation into the underlying causes of sudden cardiac death (SCD) a surreptitious killer of hundreds of thousands annually in the United States researchers have discovered a variation in the genome's DNA sequence that is linked to a significant increase in a person's risk of SCD.

The new finding flags a DNA sequence called the BAZ2B locus, a region along the genome containing three genes previously unknown to play any role in cardiac biology, according to a report published online June 30 in PLoS Genetics. Understanding how genetic variation in this region plays a role in the risk of SCD could eventually help those at risk take steps to prevent it, the researchers say, although they emphasize that a great deal of follow-up work is required.

"Our analysis suggests that if you have one copy of this variant, your increased risk is double that of someone who doesn't," says Dan Arking, Ph.D., lead author of the study and an associate professor in the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine. "If you have two copies having inherited one from each parent you have almost a fourfold increased risk of SCD."

Statistically significant though it is, this variant alone doesn't give scientists the information they need to proceed with a clinically useful test or therapy, Arking says. Scientists first need to figure out which of the three genes in the region is the key player, and determine how that gene's function is compromised likely by using model organisms to investigate their heart-related biological activity.

To identify the variant, a consortium of researchers first combined five separate genome wide association studies to survey each of the 3 billion base pairs in the DNA sequences of 1,283 individuals of European ancestry who experienced SCD, and more than 20,000 individuals without SCD. They followed up suggestive findings in an additional 3,119 SCD cases and 11,146 non-SCD control subjects from 11 European ancestry studies to confirm that the BAZ2B locus is associated with SCD.

Collecting enough DNA samples to yield statistical power has been a challenge for investigators studying SCD, Arking says. One reason is that most individuals who experience it do not have clinical signs that would suggest that they are at high-risk for SCD. In addition, only about 10 percent of people survive their initial sudden death events. (Even if the heart stops beating, a person might be saved if the heart is shocked quickly enough back into normal rhythm. The episode is still considered a sudden death event, even if the person survives, because death would have occurred without intervention.)

"SCD is a distinct disorder that involves an electrical instability in the heart," Arking says. "It's what happens when a 40-year-old guy one minute is feeling great, working out on a treadmill, and the next minute, without warning, drops dead."

Arking emphasized that based on their analyses, plenty of people are walking around with the BAZ2B variant who don't experience sudden death. SCD is a complex disease, he says, meaning this newly identified risk factor is neither necessary nor sufficient as its cause. The variant is independent of other risk factors for sudden cardiac death, which include diabetes, heart attack, and a prolonged QT interval, a measure of electrical activity in the heart obtained from a standard electrocardiogram (ECG).

"While we've done a great job of treating coronary disease and reducing the risk of heart attacks, we've made very little progress in reducing the risk of sudden cardiac death," Arking says. "The use of genetics to screen broadly is critical because we don't have other measures that will do a good job of identifying people at risk."


'/>"/>

Contact: Maryalice Yakutchik
myakutc1@jhmi.edu
443-287-2251
Johns Hopkins Medical Institutions
Source:Eurekalert

Related biology news :

1. Johns Hopkins researchers awarded $32 million
2. Johns Hopkins scientists expose cancer cells universal dark matter
3. Johns Hopkins researchers link cell division and oxygen levels
4. Johns Hopkins scientists reveal nerve cells navigation system
5. Texas researcher Arthur E. Johnson to give prestigious ASBMB-Lipmann Lectureship
6. Johns Hopkins team creates stem cells from schizophrenia patients
7. Johns Hopkins researchers capture jumping genes
8. Encyclopedia of Life names Dr. Rebecca Johnson a 2011 Rubenstein Fellow
9. Johns Hopkins researchers reshape basic understanding of cell division
10. UNCs Dr. Sean McLean receives Robert Wood Johnson Foundation award
11. American Society for Microbiology honors Ryan Johnson
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/23/2017)... the first robotic gym for the rehabilitation and functional motor sense evaluation ... Genoa, Italy . The first 30 robots will be available from ... . The technology was developed and patented at the IIT laboratories ... Technology thanks to a 10 million euro investment from entrepreneur Sergio Dompè. ... ...
(Date:4/19/2017)... York , April 19, 2017 ... as its vendor landscape is marked by the presence ... market is however held by five major players - ... Together these companies accounted for nearly 61% of the ... the leading companies in the global military biometrics market ...
(Date:4/11/2017)... Fla. , April 11, 2017 ... and secure authentication solutions, today announced that it ... Intelligence Advanced Research Projects Activity (IARPA) to develop ... Thor program. "Innovation has been a ... IARPA,s Thor program will allow us to innovate ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... ... 12, 2017 , ... The Blavatnik Family Foundation and the ... of the 2017 Blavatnik Regional Awards for Young Scientists. Established in 2007, ... the New York Academy of Sciences to honor the excellence of outstanding postdoctoral ...
(Date:10/12/2017)... ... October 12, 2017 , ... ... genomics analysis platform specifically designed for life science researchers to analyze and ... researcher Rosalind Franklin, who made a major contribution to the discovery of ...
(Date:10/11/2017)... , ... October 11, 2017 , ... ... announced today it will be hosting a Webinar titled, “Pathology is going digital. ... Associates , on digital pathology adoption best practices and how Proscia improves lab ...
(Date:10/11/2017)... ... October 11, 2017 , ... Singh Biotechnology today ... designation to SBT-100, its novel anti-STAT3 (Signal Transducer and Activator of Transcription 3) ... able to cross the cell membrane and bind intracellular STAT3 and inhibit its ...
Breaking Biology Technology: