Naked mole rats reveal genetic secret to long life

They’re strange, bald underground rodents that look like sausages with teeth, and they’ve just revealed the genetic secret to long life.

A new study of the strange naked mole rat shows that the animals have evolved a DNA repair mechanism that could explain their longevity.

These burrow-dwelling rats have a maximum lifespan of almost 40 years, making them the longest-living rodent in the world.

The new findings, published in the journal Science, could also explain why naked mole rats are resistant to a wide range of age-related diseases.

Animals are resistant to cancer, brain and spinal cord deterioration, and arthritis, so many scientists want to better understand how their bodies work.

For this study, led by a team from Tonji University in Shanghai, China, the focus was on DNA repair, a natural process in our body’s cells. When strands of DNA – our genetic building blocks – are damaged, a mechanism is triggered by which another undamaged DNA strand is used as a template to repair the break.

This research focused on a particular protein involved in this damage detection and repair system.

When a cell detects damage, one of the substances it produces is a protein called c-GAS. This plays several roles, but what interested these scientists is that in humans it interferes and hinders the process by which DNA is put back together.

Scientists believe this interference could promote cancer and shorten our lifespan.

However, in naked mole rats, researchers found that the same protein did exactly the opposite. It helps the body repair DNA strands and keep each cell’s genetic code intact.

Professor Gabriel Balmus studies DNA repair and aging at the University of Cambridge. He said the discovery was exciting and “the tip of the iceberg” when it comes to understanding why these animals live so extraordinarily long.

“You can think of cGAS as a piece of biological Lego – the same basic shape in humans and naked mole rats, but in the mole rat version a few connectors are reversed, allowing it to assemble an entirely different structure and function.”

Over millions of years of evolution, Professor Balmus explained, naked mole rats appear to have rewired the same path and “used it to their advantage”.

“This discovery raises fundamental questions: How did evolution reprogram the same protein to act in reverse? What changed? And is this an isolated case or part of a larger evolutionary pattern?”

More importantly, scientists want to know what they can learn from these rodents to improve human health and prolong quality of life as we age.

“I think if we could reverse engineer the biology of the naked mole rat,” Professor Balmus said, “we could bring much-needed therapies to an aging society.”