Researchers at the University of Edinburgh say they have identified DNA variants that can cut a person’s life span by up to 3 years. The two changes are relatively common in the human population and more than two-thirds of us will inherit a single copy of one of them from either our mother or father.
Having a copy of one variant may reduce expected lifetime by up to a year, according to the study (“Variants Near CHRNA3/5 and APOE Have Age- and Sex-Related Effects on Human Lifespan”), published in Nature Communications. Around 3 in 1000 people will inherit two copies of both variants and can expect to die an average of 3 years earlier.
One of the variants is linked to a gene associated with an increased risk of lung cancer and severe respiratory problems in people who smoke. The other is in a gene associated with Alzheimer’s disease and high cholesterol.
The research also found that the variants had different effects on men and women’s life spans. The gene change linked to Alzheimer’s disease had a greater effect on women, whereas the variation associated with lung disease had greatest effect on men. The team made the discovery by analyzing genetic information from more than 152,000 people who participated in the UK Biobank study.
Peter Joshi, Ph.D., of the University of Edinburgh’s Usher Institute of Population Health Sciences and Informatics, noted that “Although the effect of these genetic variants on lifespan is surprisingly large, it is important to remember that this is only part of the story. Lifestyle has the greatest impact on how long we live and that is under our control.”
“These discoveries are the tip of the iceberg. As more data become available later this year, we expect to see many more discoveries. Excitingly, some of these might have a beneficial effect on health,” added Jim Wilson, Ph.D., also of the University of Edinburgh’s Usher Institute of Population Health Sciences and Informatics.