Radiation likely hasn’t caused the genetic differences seen between two dog populations near the Chernobyl Nuclear Power Plant (NPP), according to a new study published in PLOS ONE.
Researchers from North Carolina State University and Columbia University explored the genetics of these dogs to understand how environmental contamination impacts living beings over time.
The study focused on two groups of dogs living just 16 kilometers (about 10 miles) apart: one near the Chernobyl NPP and the other in Chernobyl City. Despite the short distance, the dogs are genetically distinct.
The researchers wanted to know if long-term, low-level exposure to toxins like radiation or heavy metals might explain these differences.
Matthew Breen, a professor at NC State and the study’s lead author, explained that the team first identified 391 key regions in the dogs’ genomes that differed between the two populations.
Some of these regions were related to DNA repair.
The next step was to take a closer look at their genomes to search for evidence of mutations caused by exposure to radiation.
The team analyzed the dogs’ DNA in detail, starting with large chromosomal differences and zooming in to examine smaller genetic changes.
They specifically searched for germ line DNA mutations—changes passed down from parent to offspring over many generations.
If radiation had caused mutations that gave some dogs a survival advantage, those mutations should still be visible, even after more than 30 generations since the 1986 Chernobyl disaster. But no such mutations were found.
“While these dogs are many generations removed from the time of the disaster, we expected mutations, if they existed, to still be detectable,” Breen said. “But we didn’t find evidence of that.”
The researchers suggest that the differences between the two populations may have more to do with survival pressures shortly after the disaster.
Dogs that already had traits to help them survive may have passed those traits down to their offspring. Over time, the two groups likely remained separate, leading to their distinct genetic profiles.
Megan Dillon, a Ph.D. student at NC State and the study’s lead author, explained, “It’s possible that only dogs with the right traits for survival bred and passed on their genes. This is something we’re looking into next.”
This research highlights the complex ways environmental disasters affect animals and humans. Co-author Norman Kleiman from Columbia University pointed out that toxins other than radiation—like heavy metals and pesticides—may also play a role in shaping health risks.
“These findings remind us how important it is to study the health effects of large-scale disasters,” Kleiman said. “With more industrial and technological advances, future disasters are inevitable, and understanding their impact is crucial for protecting both people and animals.”
The team also discovered differences in ticks found on dogs at the two locations and the diseases those ticks carry. These findings, published in the journal Parasites and Vectors, reflect how animals’ environments can shape their exposure to pathogens.
Studying these dogs provides valuable insights into how humans might be affected by similar environmental conditions, making this research critical for public health.
