If a simple blood test could tell you how long you have left to live, would you do it? That test already exists, and soon, it will be backed up by enough research to make it useful for everyone. Because there’s a catch: You can change your fate.
Cholesterol, glucose, blood pressure are all biomarkers that can give hints as to whether a person will get sick and possibly even die young. But in 1985, biological researcher Elizabeth Blackburn discovered something that is just now starting to change the way we think about life span: telomerase, an enzyme that helps lengthen telomeres--structures that protect chromosomes in all living beings. When cells divide, these DNA stretches get shorter. And when they get too short, risks for various diseases increase.
Since Blackburn’s discovery, short telomere length has been linked to everything from coronary heart disease to cancer. As research builds up, so do indications that longer telomeres are harbingers of a longer lifespan.
In the past few years, a number of companies have popped up offering to test people’s telomeres Telome Health, a Bay Area-based company co-founded by Blackburn, is among them (though only individuals participating in research studies can avail themselves of Telome’s services at the moment).
I recently saw Dr. Elissa Epel, a founding member of Telome Health and associate professor of psychiatry at UCSF, speak about the future of telomeres at Singularity University’s FutureMed event. "Just one blood draw around mid-life is predictive of diseases of aging," she says. Epel speculates that telomeres could one day even be used to predict drug response: "It’s potentially a marker for how people do in treatment. It may be helpful for medical decisions."
It all sounds a little too strange to be true, and the research does have its skeptics. Carol Greider, a molecular biologist who won the 2009 Nobel Prize for her work on telomeres along with Blackburn, told the New York Times in 2011 that "A given telomere length can be from a 20-year-old or a 70-year-old … You could send me a DNA sample and I couldn’t tell you how old that person is.” Now that telomere testing is becoming more widespread, there’s a window for researchers to look at telomere length averages throughout life. That way, telomere testing companies can provide context for results. Telome Health is tracking telomeres of 500 healthy people between 20 and 79 to get a better sense of telomere norms at various ages.
The next question that will come out of someone’s mouth once they realize they have short telomeres: What can be done? "Telomere length is modifiable … it’s really sensitive to the way we live," says Epel. At FutureMed, she rattled off a list of factors that are linked to telomere length. Things like smoking, stress, and exposure to trauma can shorten telomeres, while taking antioxidants, exercising vigorously, and meditation can potentially lengthen them. The only problem is that no one is really sure just how much telomere length can be controlled by different factors.
Epel is the director of UCSF’s AME Center (Aging, Metabolism, Emotion), which is currently running telomere-related studies to shed some more light on how these DNA segments work. The Stress Aging and Emotions study is examining the stress levels of mothers with autistic kids along with telomere length. The researchers will stage interventions to try to reduce stress, and in turn possibly lengthen the participants’ telomeres. Another study at the AME Center is looking at whether telomeres can be lengthened by exercise interventions in sedentary young and middle-aged adults.
Epel predicts that by 2015, telomere length will be looked at as a solid risk factor for disease, much like cholesterol. In 10 years, she thinks it will be a common in-office test. Whether or not it’s ethical to tell people their telomere length is something that will be left up to the humans of the near future.