A new blood test that will come on the market later this year in over-the-counter form is raising questions about just how much we should know, and what will be done with that knowledge. The test will, the maker says, be able to predict your life expectancy to within a decade.
The test, by the company Life Length, is to come on the market in the U.K. later this year, and will cost 500 euros ($714). The tests measures the length of a person's telomeres, the cap-like molecular structures on the tips of the chromosomes. The shorter they are, scientists believe, the nearer one is to death.
Essentially, the test will give a person's "true" biological, vs. his chronological, age. There have been tests that estimate your biological age based on answers to questions about lifestyle and medical conditions, but this is the first such blood test to hit the over-the-counter market.
Maria Blasco of the Spanish National Cancer Research Centre in Madrid, who is the inventor of the new telomere test said,
"We know that people who are born with shorter telomeres than normal also have a shorter lifespan. We know that shorter telomeres can cause a shorter lifespan. But we don't know whether longer telomeres are going to give you a longer lifespan. That's not really known in humans.
"What is new about this test is that it is very precise. We can detect very small differences in telomere length and it is a very simple and fast technique where many samples can be analysed at the same time. Most importantly, we are able to determine the presence of dangerous telomeres – those that are very short."
Professor Jerry Shay of the University of Texas Southwestern Medical Centre in Dallas is a scientific consultant for Life Length. He said,
"This test devised by Blasco is so accurate that it is likely to provide more useful information than some of the other tests out there right now. What's important in ageing is the shortest telomeres. What makes cells stop growing is the shortest telomeres, not the average telomere length, which is what other tests look at.
"Everyone talks about the chronological age, but there is also a biological age, and telomere length is actually a pretty good representation of your biological age. Telomeres are important – there is no question of that."
There is concern that insurance companies may start requesting telomere tests for their customers. But also, there is skepticism among some scientists.
Blasco is one the former students of Johns Hopkins University researcher Carol Greider, who won a share of the 2009 Nobel Prize in Medicine for discovering the telomere-affecting enzyme telomerase. Greider had been offered a position on Life Length's board of advisers, which could have been a lucrative position paying $30 - $50,000 annually, but she declined even before compensation was discussed. Greider said,
“I think they’re just trying to make money. I couldn’t participate in what they were standing for. The science isn’t there yet.”