SCIENCE
Dear old dad may be responsible for more than just your facial features. As a recent study suggests, the risk for heart disease may be passed from father to son.
In general, men get heart disease 10 to 15 years earlier and twice as often as women. After menopause, the risk of heart disease in women approaches that for men. As a result, heart disease is the leading killer of both men and women, according to the Centers for Disease Control.
A recently published study explored the specific role of the Y chromosome in coronary artery disease to explain why men are more commonly affected than women.
The study was the first to determine the possible association between the Y chromosome and coronary artery disease, including an examination of underlying risk factors.
The research team, working at the University of Leicester (U.K.), has discovered that the risk for heart disease may be passed from father to son. Published in The Lancet earlier this year, the study analyzed data on genetic markers collected in 1995 for more than 3,200 men enrolled in heart disease studies across the U.K.
The Y chromosome is one of two chromosomes that determine sex in humans. Only present in males, the Y chromosome contains the smallest number of genes of all human chromosomes. It is normally transmitted unbroken from father to son.
The deep-seated biological role of the Y chromosome is to pass on male characteristics. Thus males possess one X and one Y chromosome, whereas women have two X chromosomes.
Nevertheless, there is also data linking the Y chromosome to the cardiovascular system. This was exemplified in abnormal polysomy of the Y chromosome (when the Y chromosome is present more than twice in a single individual), which is associated with increased cardiovascular mortality.
Researchers discovered that men possessing a specific genetic variant were 50 percent more likely to have coronary artery disease than men without it. Furthermore, this increased risk was independent of other known contributing factors such as smoking, high cholesterol, high blood pressure, age and weight.
Such a genetic link is not entirely surprising, given that heart disease has been known to run in families. However, it is unclear how this particular genetic signature is involved.
Researchers have speculated that this is likely due to its influence on inflammation and immunity. As Scientific American reported, the genetic variant came with many altered patterns of regulation in immune pathways. These differences might play a role in atherosclerosis, or the hardening of the arteries, which is related with heart disease.
Association of coronary artery disease and this genetic variant offers an interesting opportunity for further scientific research. Principal investigator Maciej Tomaszewski commented in a statement on the significance of these recent results in giving new meaning to the role of the Y chromosome:
“The major novelty of these findings is that the human chromosome appears to play a role in the cardiovascular system beyond its traditionally perceived determination of male sex.”
While the research findings offer powerful new information, they do not suggest that the genetic variant is completely, or even mostly, responsible for the total risk of heart disease in men. Likewise, Y chromosome scanning is not sufficient to predict an individual man’s risk of developing coronary artery disease.
However, as the researchers have pointed out, these findings could have important public health implications, especially toward evaluating the occurrence of the disease within a population.
