New research discovers genetic defect linked to African Americans with heart failure

March 7, 2018, University of South Florida
Stephen Liggett, MD, professor of internal medicine and vice dean for research at the University of South Florida Morsani College of Medicine, Tampa, Fla., led the first genetic study of its kind to examine the genetic basis of heart failure in African Americans. Credit: University of South Florida

Heart failure is more common, develops earlier and results in higher rates of illness and death in African Americans than in whites.

Now, the first genetic study of its kind to examine the genetic basis of failure in African Americans, led by the University of South Florida (USF), Tampa, Fla., has identified a linked specifically to heart failure in this population. The discovery could lead to more precise and effective treatments for African Americans, who are more likely to suffer from a common form of heart failure of unknown cause called idiopathic dilated cardiomyopathy (IDC). IDC is a condition in which the heart weakens, cannot pump blood properly and becomes progressively enlarged.

The study was published Feb. 26 in the Journal of Personalized Medicine.

"We know that this form of heart failure has a worse prognosis in African Americans and does not respond as effectively to most therapies as compared to the same treatments in Caucasian individuals of European descent. Yet, there had never been a genome-wide association study performed exclusively in African Americans," said senior author and project director Stephen B. Liggett, MD, professor of internal medicine and vice dean for research at the USF Health Morsani College of Medicine.

"We undertook this study because of the severe under-representation of African Americans in these types of trials, and, our idea that the genetic causes might be different in this population," Dr. Liggett added. "Our genome-wide analysis suggests that is indeed the case, and we may need to develop new drugs to target IDC in African Americans."

The Genetics of African American Heart Failure consortium examined genetic variations in the genomes of 662 African-American patients recruited from five U.S. academic medical centers: the University of Cincinnati College of Medicine, Duke University School of Medicine, Johns Hopkins University School of Medicine, University of Maryland College of Medicine, and the Virginia Commonwealth University School of Medicine. All the study participants had no history of heart attacks and were diagnosed with IDC.

The researchers found that a variation in one gene, called CACNB4, could contribute to causing IDC in African Americans. That same genetic defect has not been found in white patients with IDC. More study is needed, Dr. Liggett said, but CACNB4 plays a key role in regulating calcium signaling important for cardiac muscle contraction, so a variation that interferes with the gene's function may lead to diminished pumping of blood by the heart.

In addition, variations in other genes suggested an association with IDC in individuals with African-American ancestry. So, the researchers mapped the biochemical pathways of these 1,000 genes, which created a network indicating the potential action by which these variations lead to IDC, and possible targets for new drugs. The consortium's analysis showed that genetic variations in African Americans account for 33 percent of the risk for IDC. And, many genes forming the pathway map were involved in how calcium regulates the work of .

Dr. Liggett and his collaborators use various research methods, including examining in different ethnic groups, with the aim of understanding how to best devise for treatment or prevention of heart failure. "Every time we perform these genetic studies, we learn something new and find another piece of the puzzle," he said, "Ultimately the dissection of this cardiovascular disease will lead to drugs that strike at damaging pathways with a high level of precision, resulting in personalized for heart ."

Nearly 6 million people in the United States have , a figure projected to increase to 8 million by 2030, according to the American Heart Association. The five-year mortality rates range from 30 to 50 percent, greater than for some cancers.

Explore further: Low levels of hormone in African-Americans may increase hypertension

More information: Huichun Xu et al, A Genome-Wide Association Study of Idiopathic Dilated Cardiomyopathy in African Americans, Journal of Personalized Medicine (2018). DOI: 10.3390/jpm8010011

Related Stories

Low levels of hormone in African-Americans may increase hypertension

June 10, 2015
Although hypertension is more common in African-Americans, they have significantly lower levels of a hormone produced in response to cardiac stress than white and Hispanic individuals, a finding that may indicate a target ...

Stubborn inequities in heart health persist for some African Americans in the South

August 15, 2016
Though mortality from heart disease is decreasing, some groups are at increased risk for developing heart disease, including African Americans in the southeastern U.S. Nearly 44 percent of all African American men, and 48 ...

African Americans live shorter lives due to heart disease and stroke

October 23, 2017
The average lifespan of African Americans is significantly shorter than white Americans, mostly because of heart disease and stroke, which contributed to more than two million years of life lost among African Americans between ...

Study identifies two new genes responsible for Alzheimer's disease among African-Americans

October 25, 2016
Researchers have identified two new genetic risk factors for Alzheimer's disease (AD) among African Americans.

Flu shot may curb respiratory infections in people with heart failure

February 2, 2017
(HealthDay)—Flu and pneumonia vaccines may reduce heart failure patients' risk of dangerous respiratory infections, a new review suggests.

Recommended for you

Caffeine from four cups of coffee protects the heart with the help of mitochondria

June 21, 2018
Caffeine consumption has been associated with lower risks for multiple diseases, including type II diabetes, heart disease, and stroke, but the mechanism underlying these protective effects has been unclear. A new study now ...

New cellular pathway helps explain how inflammation leads to artery disease

June 21, 2018
Investigators have identified a new cellular pathway that may help explain how arterial inflammation develops into atherosclerosis—deposits of cholesterol, fats and other substances that create plaque, clog arteries and ...

'Smart stent' detects narrowing of arteries

June 19, 2018
For every three individuals who have had a stent implanted to keep clogged arteries open and prevent a heart attack, at least one will experience restenosis—the renewed narrowing of the artery due to plaque buildup or scarring—which ...

Marriage may protect against heart disease / stroke and associated risk of death

June 18, 2018
Marriage may protect against the development of heart disease/stroke as well as influencing who is more likely to die of it, suggests a pooled analysis of the available data, published online in the journal Heart.

Deaths from cardiac arrest are misclassified, overestimated

June 18, 2018
Forty percent of deaths attributed to cardiac arrest are not sudden or unexpected, and nearly half of the remainder are not arrhythmic—the only situation in which CPR and defibrillators are effective—according to an analysis ...

Tick-borne meat sensitivity linked to heart disease

June 15, 2018
University of Virginia School of Medicine researchers have linked sensitivity to an allergen in red meat—a sensitivity spread by tick bites—with a buildup of fatty plaque in the arteries of the heart. This buildup may ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.