Researchers in Massachusetts have discovered a host of genetic variations that may be responsible for living past 100. Thomas Perls, director of the New England Centenarian Study, and colleagues examined the genes of 1055 people over the age of 100 and compared them to 1267 controls. As discussed recently in Science, the scientists found 150 single nucleotide polymorphisms (SNPs) that were linked to longevity. Using these genetic markers, they could predict whether a random genome belonged to a centenarian with 77% accuracy. We are now one step closer to understanding which genes code for long life and leveraging these findings to provide longevity for everyone.
As we discussed in our earlier conversation about living past 100, below the age of about 80, lifestyle choices seem to play a dominant role in determining who lives and dies. Yet if you want to live past 90, 100, or 110, having the right genes seems to be a huge requirement. Right now, scientists are merely trying to determine which genes are relevant. Once that list is established, scientists could study the associated proteins for each gene and possibly develop some means to extend their benefits of long life to the general population.
Interestingly, many centenarians have the same genetic disposition to geriatric diseases as non-centenarians. Yet many of those who live past 100 don't develop age-related illnesses (with the exception of poor eyesight and arthritis) until their very last years. There is something, then, in their other genes that act as a kind of shield against poor health.
Using the 150 SNPs, Perls and his associates were able to build genetic profiles for a typical centenarian. 90% of those examined who lived past 100 would fit one of these 19 profiles. 45% of those that lived past 110 had even higher proportions of the SNPs associated with longevity. Looking at their control cases, Perls and company think that about 15% of people have a profile for becoming a centenarian. These are extraordinary finds. With that information we could study your genome and make a fairly accurate prediction about whether or not you'll have a natural tendency towards longevity or even super longevity (110+ years).
Or we could...if you're Caucasian in the Northeast US. Like many such projects, the New England Centenarian Study is focused on a demographic that is relatively narrow in terms of geography and ethnicity. It is likely that there are other sets of SNPs, and other genetic profiles that could be derived for other regions and ethnic groups. We've actually seen other research, like the Okinawa Centenarian Study, which has shed light on longevity factors in other regions. In general it will take the effort of many more researchers like Perls working all over the globe before we could build a definitive understanding of which genes are linked to longevity in the general population. But that work is coming.
As we wait for genetics to reveal more about the path to longevity, there are many things that you can do to extend your own expected lifespan. A study of regions where people routinely live past 100, the Blue Zones of the world, reveal common lifestyle choices: eating right, getting exercise, and avoiding stress through loving relationships. Perls has built a website, LivingTo100, that will give you a questionaire to judge how your lifestyle choices may be affecting your longevity. Try it out to get a sense of what simple things (quitting smoking, eating less processed meats, etc) could help you live longer.
Research about longevity is still in its early stages and for now most of the responsibility for living a long life is still on you. Eventually, however, we'll find ways to extend life no matter how you live or what genes you were born with. Along with regenerative medicines aimed at repairing or replacing body parts injured in accidents, longevity research is helping us move towards the possibility of effective immortality. Those with centenarian genes who are born today may live well beyond 100, 200, or even 1000 years. And they won't be alone.
[image credit: The Sun]
[source: Sebastiana et al, Science 2010]