that the Y chromosome contains more genes than previously thought — whose jobs are not fully known.
In parallel with that work, research has linked a loss of Y to various disease risks.
To get at the why, Walsh and his team conducted studies in both humans and lab mice.
For the former, they used a large research database with medical and genetic information on about 500,000 British adults. They found that men who entered that study with a significant loss of Y — in over 40% of their blood cells — fared worse over the ensuing years.
They were 41% more likely to die of any cause over the next seven years, versus men without loss of Y. Specifically, they were about two to three times more likely to die of heart failure or heart disease related to longstanding high blood pressure.
To directly test the effects of Y loss, Walsh’s team used “gene-editing” technology to create lab mice that lacked the chromosome in many of their blood cells.
They found that in aging male mice, Y loss sped up age-related changes in heart structure and function, and made the animals more vulnerable to scarring in the heart, as well as the lungs and kidneys. In one experiment, the chromosome loss made existing heart failure worse.
Walsh says that Y chromosome loss appeared to alter the function of immune cells that operate in the heart, leading to tissue scarring.
RELATED: Ten Health Symptoms Black Men Shouldn’t Ignore
Screening men for the loss of Y?
While the loss of Y sounds like it can have damaging effects on your health, the good news is this study could spur more interest in a phenomenon that has gotten relatively little attention, one researcher notes.
There is “exciting potential” for discovering new therapies for common diseases of aging, says Kim Simpfendorfer, an assistant professor at Feinstein Institutes for Medical Research in Manhasset, N.Y.
It may even be possible, she says, to screen men for