SANTA ANA, Calif.—If you lead an active, extroverted life and are something of a thrill seeker, you might be genetically primed to live into your 90s or longer, according to a new study by a team that included University of California, Irvine researchers.
A variation of a much-studied gene involved in transmission of dopamine, a key component of the brain’s reward and learning system, was found to be far more frequent among the very old.
And the same gene variant was also linked to longer life in mice.
The variant itself might not extend lifespan directly, said Robert Moyzis, a UCI biological chemistry professor and an author of the study.
Instead, it appears to predispose those who bear it to a more vigorous lifestyle.
“This particular variation has already been associated with personality traits that are much more outgoing, much more socially engaged,” Moyzis said. “We think it’s a simple as that. Obviously, if you are much more likely to be engaged in physical and intellectual activities as you age, there have been many studies that have shown that is a good predictor of adding a few more years to your life.”
The human subjects in the study came from Laguna Woods, part of a group involved in the Leisure World Cohort Study that began in 1981. It included people who were 90 years old or older in 2003; most of them have since passed away, Moyzis said.
But their genes, as well as cell lines, live on, perpetuated in laboratories so they will be available for a variety of research projects.
In this study, genetic samples from 310 people 90 years old or older were checked for the gene variant, known as the DRD4 7R allele.
Sixty-six percent more people possessed the gene variant in the 90-plus group when compared with a control group of nearly 3,000, aged seven to 45.