A University of Colorado scientist who proved the link between genetics and longevity, leading to breakthroughs in age-related diseases like Alzheimer’s, died earlier this year.
Tom Johnson discovered that manipulating a gene in roundworms could extend their lifespan by more than 50%. His groundbreaking research formed the foundation for a new scientific field called geroscience, or the study of the aging process.
When Johnson began his career in the 1970s, the search for a genetic link to longer life was considered junk science, said Simon Melov, who worked with Johnson as a postdoctoral fellow in the 1990s. Melov recalled asking a mentor for advice prior to joining Johnson’s lab.
“And he told me, ‘Don't waste your time going there. Nobody believes in that guy. He's crazy,’” said Melov, now a professor at the Buck Institute for Research on Aging in California.
“It was thought that aging just happens and it's just some sort of random thing,” he said.
Then Johnson showed he could create roundworm superagers, by working with a gene he named age-1.
Melov called the discovery a “game changer.”
“By the late ‘90s, people were doing this in all sorts of organisms, including mice, and the field continued to expand beyond this kind of niche little area,” he said.
Roundworms, or C. elegans, are simple creatures, but are helpful in research because of their genetic overlap with more complex beings. More than 80% of C. elegans genes have related genes in humans.
Today, science that builds on Johnson’s work is making strides in understanding aging. Melov’s research focuses on senescent cells, which wreak havoc on aging bodies, driving inflammation and disease. Treatments to combat those cells are known as senolytics.
Another of Johnson’s colleagues, CU’s Christopher Link, works to understand age-associated neurodegenerative diseases such as Alzheimer’s.
One thing Johnson’s work did not do, Melov cautioned, is promise a genetic switch for a fountain of youth. For one thing, humans have “thousands” of genes related to longevity, he said. For another, genes aren’t destiny. Environment and healthy habits still play an important role.
“It's certainly under our control to modulate our health span and our lifespan to a large extent,” Melov said.
“I mean, you have no control over your parents, but if you have long-lived parents, then the chances are that you will be long-lived, assuming you don't drink every day and smoke a couple of packs of cigarettes every day,” Melov explained.
“And so conscious monitoring of those sorts of things will enhance the likelihood that you can benefit from having a good genome.”
“And if you had short-lived parents, you maybe should think about exercising regularly and giving up the cocktail every night or something,” he said.
Tom Johnson passed away earlier this year at the age of 77. Melov said the man known as “the father of genetic gerontology” wasn’t necessarily obsessed with living forever.
“Tom was always just a curious person. He was very, very good at just following his nose. And in general, he just had a boundless curiosity about working in science. I mean, he loved science. He was very passionate about his work in general, and just enjoyed being a scientist,” he said.
| This story is a part of Aging Matters, a series from Colorado Matters about the Centennial State's aging population. Read more stories here. |
