The loss of the male sex chromosome as men age leads to earlier death and could help explain why they do not live as long as women, new research has suggested.
According to the study, the loss of the Y chromosome causes the heart muscle to scar and can lead to deadly heart failure.
The research suggests that men who suffer from this loss – estimated to include 40% of 70-year-olds – may benefit from an existing drug that targets dangerous tissue scarring.
The drug, called pirfenidone, may help counteract the harmful effects of the chromosome loss, University of Virginia (UVA) researcher Kenneth Walsh said.
Chromosomes – the bundles of DNA in each cell – come in pairs and while women have two X chromosomes, men have an X and a Y chromosome.
Prof Walsh, the director of UVA’s Hematovascular Biology Centre, said: “Particularly past age 60, men die more rapidly than women.
“It’s as if they biologically age more quickly.”
He added: “This new research provides clues as to why men have shorter lifespans than women.”
According to researchers, many men begin to lose their Y chromosome in a fraction of their cells as they age, and this appears to be particularly true for smokers.
Scientists have previously found that men who suffer Y chromosome loss are more likely to die at a younger age and suffer age-associated conditions such as Alzheimer’s disease.
However, the new research is believed to be the first hard evidence that the chromosome loss directly causes harmful effects on men’s health.
Researchers used gene-editing technology to develop a special mouse model to better understand the effects of Y chromosome loss in the blood.
They found that the loss accelerated age-related diseases and made the mice more prone to heart scarring and led to earlier death.
Additionally, the researchers looked at the effects of Y chromosome loss in human men.
They conducted three analyses of data compiled from the UK Biobank study and found that Y chromosome loss was associated with cardiovascular disease and heart failure.
As chromosome loss increased, so did the risk of death, the scientists found.
They say the findings suggest that targeting the effects of Y chromosome loss could help men live longer, healthier lives.
The findings are published in the Science journal.
