March 9 (UPI) -- Researchers have identified the genetic basis of heart failure in African-Americans, which may lead to more precise and effective treatment for the condition.
A first-of-its-kind study, led by the University of South Florida in Tampa, reveals the genetic link to heart failure of unknown cause called idiopathic dilated cardiomyopathy in African-Americans, or IDC, according to research published in the Journal of Personalized Medicine.
In IDC, the heart weakens, cannot pump blood properly and becomes progressively enlarged.
Blacks are nearly twice as likely as whites to die from preventable heart disease and stroke, according to the Centers for Disease Control and Prevention. And black men are at a greater risk than white men.
Even so, a genome study had not previously been done that specifically looked at African-Americans -- even though genetics represent 33 percent of the risk for IDC. The remaining two-thirds are environmental factors that include diet and smoking, as well as other diseases, including diabetes.
"We have had evidence from other studies and labs that there are distinct variances that occur essentially only in African-American descent," senior author and project director Dr. Stephen B. Liggett, a professor of internal medicine and vice dean for research at the USF Health Morsani College of Medicine, told UPI. "So we know there were what you call genetic substructure differences, so you don't want to do only generalized studies that are performed only in, say, European Caucasions."
In fact, there was a wide-ranging study done in Iceland, but the participants were mainly of Nordic descent.
Over 10 years, the Genetics of African American Heart Failure consortium examined genetic composition in 662 African-American women and women 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.
The study participants had no history of heart attacks and were diagnosed with IDC. A control group of 1,167 previously underwent testing and didn't have the disease. Researchers then based their results on general studies that included a variety of races.
The researchers found a gene called CACNB4 could contribute to causing IDC in African-Americans -- and the same gene has not been found in white patients with IDC.
"IDC is a little more common in African-Americans," Liggett said, noting that it is likely there are other genes specifically tied to African-American descent. "We are at a place now in medicine to not just use someone's skin color. We have technology."
The researchers also noted that heart disease is known to be prevalent in black athletes.
"It has been reported that African-American athletes exhibit a greater magnitude of left ventricular hypertrophy in response to intense physical exercise than white athletes, suggesting potential biological differences in cardiac adaptation between African Americans and Caucasians," the authors wrote.
But Liggett cautions that it would be wrong for teams to consider using the genetic variances in consideration of an athletes' risk. "We are all going to show predisposition in certain diseases," he said.
Liggett said the researchers hope to replicate the study and confirm its results in the future, in addition to expecting the current study to potentially help develop new drugs and therapies.
"We did try to build a pathway around this gene and some other ones associated with significance with the disease," Liggett said. "It will take some additional work to establish that."