Smoking kills off the Y chromosome in men's blood cells, researchers said— a finding that may explain why men are more likely to die from smoking-related illnesses than women. They say that male smokers run higher health risks than women, whose genetic study could explain why men die from various cancers at a disproportionate rate when compared to women.
Male smokers are three times more likely than non-smoking men to lose Ychromosomes as they age, say scientists at Uppsala University in Sweden.
The Y chromosome. Men have it. Women don't. It is the Y chromosome that makes men. Researchers show that damage to the Y chromosome increases the risk of cancer in all parts of the body. This is considered to be a natural change affecting older men.
In a new study, researchers have now demonstrated that smoking contributes to the decline of Y chromosomes in blood
cells.Its long been known that as men age the Y chromosome, important for sperm production and sex determination, can begin to disappear from cells in the body, a phenomenon once considered a normal process of aging.
However, some recent studies have suggested the process might not be benign, linking Y chromosome loss to a shorter life span and an increase of cancer.
The new study, published in Science journal, found older men who are smokers typically lose more Y chromosomes from their blood cells than non-smokers do.
That may explain why cancer risks among male smokers tend to be higher than in female smokers, says study leader Lars Forsberg of Uppsala University's Department of Immunology, Genetics and Pathology.
Analyzing data on more than 6,000 men, the researchers found that the more a man smoked, the more Y chromosome loss he experienced.
The researchers also noted that in some men who successfully quit smoking there was an increase in levels of Y chromosomes as cells that had lost the chromosome disappeared from circulation.
"This discovery may be very persuasive for smokers to quit smoking," says Forsberg.
The new results may help explain why men have a lower life expectancy than women and why smoking is particularly dangerous for men, according to a news release from the university.
Smoking seems to be the main reason for damaged Y chromosomes. In the study, heavy smokers lost the most chromosomes, and if they quit, the damage was partially repaired.
Science Nordic/NBC/ZA