'Longevity Gene' That Helps Repair DNA and Extend Life Span Could One Day Prevent Age-Related Diseases in Humans

age old hands carestock getty images
Getty Images

Scientists studying longevity believe a gene could explain why some animals live longer.

In 18 species of rodents with varying life spans, researchers looked at sirtuin 6 (SIRT6), a gene that plays a role in bodily processes such as aging, cellular stress resistance and DNA repair.

Over time, DNA inevitably suffers what are known as double-strand breaks (DSBs) that can cause genes to mutate, triggering aging and diseases like cancer.

Dirk Bohmann, a professor of biomedical genetics at the University of Rochester Medical Center, explained in a statement, "[DSBs] are always going to be there, even if you're super healthy. One of the main causes of DSBs is oxidative damage and, since we need oxygen to breathe, the breaks are inevitable."

While animals with relatively short life spans don't have so many DSBs, Bohmann explained, "if you want to live for 50 years or so, there's more of a need to put a system into place to fix these breaks. The SIRT6 protein seems to be the dominant determinant of lifespan. We show that at the cell level, the DNA repair works better, and at the organism level, there is an extended lifespan."

To answer whether SIRT6 works harder in species that live longer, the team studied 18 rodents, from mice expected to live around three years to beavers and mole rats with life expectancies of up to 32 years. Animals with stronger SIRT6 proteins were found to live longer.

This was also apparent when they compared the molecular differences in the SIRT6 proteins of mice and beavers. And by dosing human cells and fruit flies with the SIRT6 from a mouse and a beaver, as expected, the scientists found the beaver protein was more potent than the mouse protein.

Vera Gorbunova, a professor of Biology at the University of Rochester, explained in a statement that the team pinpointed five amino acids that appear to make the SIRT6 protein stronger and "more active in repairing DNA and better at enzyme functions."

The researchers concluded that the more robust ability to repair double-strand breaks co-evolved with longevity. The findings were published in the journal Cell.

"The capacity of the SIRT6 protein to promote DSB repair accounts for a major part of the variation in DSB repair efficacy between short- and long-lived species," the authors wrote.

The team will now study the SIRT6 of animals with extremely long life spans, including the bowhead whale, which can live for over 200 years.

This ongoing work, the researchers hope, could form the basis for anti-aging treatments.

"The ultimate goal is to prevent age-related diseases in humans. If diseases happen because of DNA that becomes disorganized with age, we can use research like this to target interventions that can delay cancer and other degenerative diseases," according to Gorbunova.

In a separate paper published in the journal Nature Communications earlier this year, a team of scientists took a different approach to the study of aging. They found the Angelica keiskei koidzumi plant, commonly known as ashitaba, used in traditional Asian medicine contains a compound that could slow this process.

The researchers identified the flavonoid 4,4′-dimethoxychalcone, which they described as a "natural compound with anti-aging properties," in the plant.