To what extent do our genes really dictate longevity?
A long-held belief has it that some people have "better genes" than others, which predisposes them to living longer lives. A large new study, however, questions the accuracy of this idea.
Scientists from Calico Life Sciences, a research and development company — in collaboration with colleagues from Ancestry, an online genealogy resource — have recently analyzed data from millions of people to establish whether genetic makeup really does have a crucial say in longevity.
The study's lead author is Graham Ruby, who is affiliated with Calico Life Sciences.
Ruby and team studied the family trees of over 400 million people and found that genes have a lower impact on how long a person can expect to live than scientists had previously believed.
Their findings now appear in GENETICS, the journal of the Genetics Society of America.
The role played by genes may be minimal
The researchers used data from the Ancestry website and focused on heritability, which measures to what extent genetic specificities explain differences in people's individual traits.
They wanted to assess the heritability of human lifespan — that is, whether the fact that a person's parents were long-lived could predict that person's own lifespan.
Furthermore, the scientists wanted to see whether any predictions of longevity would rely predominantly on genetic makeup, or on other factors altogether.
"Partnering with Ancestry allowed this new study to gain deeper insights by using a much larger dataset than any previous studies of longevity," notes study co-author Catherine Ball, who is affiliated with Ancestry.
According to the team, previous estimates indicated that human lifespan heritability ranged between 15 and 30 percent.
After looking at a carefully selected set of family trees and relevant information collected from over 400 million people surveyed by Ancestry — most of whom were of European descent and based in the United States — the investigators identified a different story.
