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

Research team traces pathway to cardioprotection in post-ischemic heart failure

December 11, 2018
During an ischemic attack, the heart is temporarily robbed of its blood supply. The aftermath is devastating: reduced heart contractility, heart cell death, and heart failure. Contributing to these detrimental changes is ...

Workplace exposure to pesticides and metals linked to heightened heart disease risk

December 11, 2018
Workplace exposure to metals and pesticides is linked to a heightened risk of heart disease in Hispanic and Latino workers, reveals research published online in the journal Heart.

Macrophage cells key to helping heart repair—and potentially regenerate, new study finds

December 11, 2018
Scientists at the Peter Munk Cardiac Centre have identified the type of cell key to helping the heart repair and potentially regenerate following a heart attack.

Study reveals new link between atrial fibrillation and mutations in heart disease gene

December 11, 2018
Atrial fibrillation (Afib), a heart condition that causes a rapid, irregular heartbeat that increases a person's risk of stroke and heart failure, is fairly common among older adults. However, its early onset form is relatively ...

Researchers have found that incidence of heart failure was around two-fold higher in people with diabetes

December 11, 2018
Researchers have found that incidence of heart failure was around two-fold higher in people with diabetes.

Study: Age, race differences determine risk of stroke in women and men

December 11, 2018
A new study found that, between the ages of 45 and 74 years, white women were less likely to have a stroke than white men, but at age 75 and older, there was no difference in stroke risk between white women and men. In contrast, ...

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.