Sex Matters: Coronary Artery Disease Risk Passed Between Males
Sex matters, especially when it comes to coronary artery disease. Along with eye and hair color, some males may pass along the risk of coronary artery disease to their sons, according to a new study published in Lancet.
Heart disease risk has a male connection
A new study found that the Y chromosome—the male chromosome—has a role in the inheritance of this most common type of heart disease. The report, entitled “Inheritance of coronary artery disease in men: an analysis of the role of the Y chromosome,” is the work of researchers at the University of Leicester.
The investigators reported on their findings of the four-year study, during which they analyzed DNA from more than 3,000 men who participated in the British Heart Foundation Family Heart Study and the West of Scotland Coronary Prevention Study. Among their discoveries was that the vast majority (90%) of British Y chromosomes fall into one of two main groups: haplogroup I and haplogroup R1b1b2.
A haplogroup is a group of similar haplotypes (specific set of DNA sequences at sites on a chromosome that are passed along together) that share common ancestral origins.
In this study, men who had a Y chromosome from haplogroup I had a 50% higher risk of coronary artery disease than other males. This risk is independent of risk factors associated with heart disease, such as obesity, smoking, high cholesterol, and high blood pressure.
Coronary artery disease (also called coronary heart disease) is characterized by the hardening and narrowing of blood vessels that transport blood to the heart. This restricted blood flow is the result of an accumulation of cholesterol and other substances (plaque) in the inner walls of the blood vessels (atherosclerosis).
Over time, coronary artery disease can weaken the heart muscle and contribute to irregular heart rhythm (arrhythmia) and heart failure.
In 2008, coronary artery disease was responsible for 88,236 deaths in the United Kingdom, according to the British Heart Foundation, affecting more men (49,665) than women (38,571). In the United States during the same year, 405,309 people died from coronary artery disease, and more than half the deaths were in men, noted by the Centers for Disease Control and Prevention.
According to Dr. Helene Wilson, research advisor at the British Heart Foundation, “This study shows that genetic variations on the Y chromosome—the piece of DNA that only men have—can increase a man’s risk of coronary heart disease.”
It’s known that males typically develop heart disease about a decade before women do, but the reason has not been determined. The results of this study suggest that sex matters, or at least the Y chromosome, when it comes to coronary artery disease, and that researchers need to “further analyze the human Y chromosome to find specific genes and variants” behind the association between sex and heart disease.
British Heart Foundation
Centers for Disease Control and Prevention
University of Leicester
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