Research on dogs living in and near the Chernobyl Exclusion Zone suggests that animals have undergone gene changes enabling them to survive in highly toxic environments.
More research is needed to prove if the changes result from adaptation or genetic drift and to see if similar changes occur in humans.
Dogs living in the Chernobyl Exclusion Zone (CEZ) may have undergone gene changes to adapt to the toxic habitat, according to a new study. Its findings could shed light on how environmental disasters impact animal and human survival.
The study marks the first documented attempt at “understanding how chronic exposure to multiple environmental hazards may have impacted these populations,” Norman J. Kleiman, Ph.D., coauthor and assistant professor of environmental health sciences at Columbia Mailman School of Public Health, said in a press release.
"Somehow, two small populations of dogs managed to survive in that highly toxic environment. "
— Norman J. Kleiman, Ph.D.
The Chernobyl disaster took place in Ukraine in 1986, when an explosion from a nuclear power plant released ionizing radiation into the air and soil, displacing about 350,000 people nearby. In the aftermath, authorities designated the CEZ as an uninhabitable area around the explosion zone, stretching about 30 km from the reactor in all directions.
Researchers evaluated and compared two groups of stray dogs in their study: one living in the CEZ and the other living in Chernobyl City, about 16.5 km from the CEZ and about 46.5 km from the reactor. The groups contained significant genetic differences, despite their close proximities, according to the researchers. Notably, the dogs living in the exclusion zone contained genes that suggested an adaptation for survival.
“The dog is a sentinel species,” Matthew Breen, corresponding study author and Oscar J. Fletcher Distinguished Professor of comparative oncology genetics at NC State, said in a press release. “By teasing out whether or not the genetic changes we detected in these dogs are the canine genome’s response to the exposures the populations have faced, we may be able to understand how the dogs survived in such a hostile environment and what that might mean for any population—animal or human—that experiences similar exposures.”
This April will mark 37 years since the explosion. And yet the damage had not been left in the past. Toxic chemicals, compounds, dangerous metals, abandoned structures, and cities contribute to the enduring environmental travesty.
“Though 37 years have passed since the accident…the danger posed by radiation exposure is still very much real,” Kleiman said in the release. “When radiation exposure is combined with a complex toxic chemical mixture of uncertain composition, there are very real human health concerns raised for the thousands of people who continue to work within the Exclusion Zone on continuing cleanup efforts as well as at two newly constructed nuclear fuel reprocessing plants.”
While it may be too early to confirm, the findings could present insight into whether and how we can adapt to such kinds of disasters.
“In future studies, we aim to determine if the genetic variation detected is indeed a biological response to enable survival after multi-generational exposures to radiation, heavy metals, organic toxins, or other environmental contaminants,” the researchers, who are affiliated with North Carolina State, Columbia University Mailman School of Public Health, University of South Carolina, and the National Institutes of Health (NIH) wrote in the study.