Nearly four decades after the Chernobyl disaster, scientists are still trying to unravel its long-term effects — not just on people, but on animals too.
Now, a new genetic study on local dogs has revealed something surprising: they’ve changed, but not in the way researchers expected.
Two populations of dogs living just 10 miles apart — one inside the nuclear exclusion zone and the other in a nearby town — are genetically distinct. That might seem logical at first. After all, one group lives where radiation levels were once off the charts. But scientists from North Carolina State and Columbia University say the differences aren’t likely due to radiation at all.
When genomes defy expectations
In earlier work, researchers found nearly 400 genetic regions that varied between the two dog populations, clearly marking them as different groups. This time, they wanted to go deeper — right down to the DNA.
In a paper published in PLOS ONE, the team explored whether years of low-dose exposure to environmental toxins — like radiation or lead — could explain the genetic divide. They focused on reproductive mutations passed from parents to offspring, zooming in from chromosome-level changes to the very building blocks of the genome.
Two groups of dogs survived highly contaminated environments. Read what researchers discovered about ‘Chornobyl Dogs.’ (#ColumbiaEHS)
➡️https://t.co/mJ0QgB5pll pic.twitter.com/iZKXA3wfYS
— ColumbiaPublicHealth (@ColumbiaMSPH) March 9, 2023
To their surprise, they found no evidence of radiation-induced genetic shifts. “We know that high doses of radiation can disrupt chromosomes,” said geneticist Matthew Breen. “And even after 30 generations, we’d expect to see signs of that if it had helped the dogs survive. But we didn’t find any.”
Evolution by survival, not radiation
So, what’s going on? One possibility, according to lead author Megan Dillon, is that dogs that managed to survive and reproduce already carried traits that made them hardier. “There might have been extreme selective pressure early on,” she explained, “and the dogs near the nuclear plant may have simply stayed isolated from the city population.”
New study examines the genetics of dogs near Chornobyl, offering insights into health risks from long-term toxin exposure after the disaster. Radiation isn’t the cause, but other environmental toxins might be. #ColumbiaEHShttps://t.co/uRZeRrbYQc
— ColumbiaPublicHealth (@ColumbiaMSPH) January 14, 2025
More research is underway to explore that idea. But scientists say one thing is already clear: these animals offer rare insight into how ecosystems — and living creatures — respond to disaster.
Why this matters beyond Chernobyl
The findings go far beyond curious canine genetics. As the researchers point out, major industrial disasters aren’t behind us — they’re likely ahead of us. And to protect both humans and animals, we need to better understand how long-term, low-level environmental exposures shape health and survival.
“The rise of technology and industrialization means we’ll see more events like Chernobyl,” the authors conclude. “And we have to be ready — with better science, better data, and better protection.”
Nathalie Mayer
Journalist
Born in Lorraine on a freezing winter night, storytelling has always inspired me, first through my grandmother’s tales and later Stephen King’s imagination. A physicist turned science communicator, I’ve collaborated with institutions like CEA, Total, Engie, and Futura. Today, I focus on unraveling Earth’s complex environmental and energy challenges, blending science with storytelling to illuminate solutions.
