Dogs living near the site of the Chernobyl nuclear disaster have mutated to develop a new superpower - they are immune to radiation, heavy metals and pollution. 

Scientists collected blood samples from 116 stray dogs living in the Chernobyl Exclusion Zone (CEZ), finding two different populations that were both genetically distinct from other dogs in the surrounding area.

This suggests they have adapted to withstand long-term exposure to this toxic environment and would explain why they have continued to thrive in the wasteland.

Understanding how the dogs developed their genetic superpower could help  better understand the health impacts of living in a highly toxic environment with multiple environmental hazards, not just in dogs but also in humans.

The Chernobyl disaster of 1986 was a nuclear meltdown that occurred in northern Ukraine. 

It began on April 26 with the explosion of one of the power plant's reactors, and led to the largest release of radioactive material into the environment in human history.

Following the tragic event, humans were evacuated from Chernobyl and the surrounding areas to avoid the extreme levels of radiation. From then on, the site was known as the Chernobyl Exclusion Zone (CEZ).

Their absence allowed wildlife to flourish and thrive in the CEZ, which contains 11.28 millirem of radiation – six times the allowed exposure amount for human workers. 

The site of the Chernobyl nuclear disaster is a radioactive wasteland. But somehow, stray dogs have managed to survive there for years, and now scientists know why.

An estimated 900 stray dogs live in the CEZ, and many of them are likely the descendants of pets left behind following the mass evacuation of Chernobyl residents.

Norman J. Kleiman, an environmental health scientist at Columbia University, led a team of researchers to investigate how living in this harsh environment impacted the dogs' genetics, as disasters that contaminate or destroy habitat can force wildlife to adapt to adverse environmental changes.

He and his colleagues collected blood samples from 116 'semi-feral' dogs, who were humanely captured around the Chernobyl Nuclear Power Plant and 10 miles away in Chernobyl City.

These samples were taken during sterilization and vaccination procedures conducted by the Clean Futures Fund Dogs of Chernobyl program in 2018 and 2019.

The blood samples were then transported to the US for DNA extraction and analysis, which revealed the dogs' unique genetic makeup.

'Somehow, two small populations of dogs managed to survive in that highly toxic environment,' Kleiman said in a statement. 

'In addition to classifying the population dynamics within these dogs . . . we took the first steps towards understanding how chronic exposure to multiple environmental hazards may have impacted these populations.' 

He and his colleagues published their findings in the journal Canine Medicine and Genetics in March 2023. 

Specifically, the researchers found nearly 400 'outlier loci,' or genomic locations that show behavior or patterns of variation that are extremely divergent from the rest of the genome.

Then, they identified 52 genes associated with these outlier loci that 'could be associated with exposure to the contamination of the environment at the Nuclear Power Plant,' the study states.

In other words, the dogs' contaminated environment caused them to develop genetic mutations that were passed down from generation to generation, ultimately driving their adaptation to the harsh conditions. 

But these strays are not the only CEZ animals found to have developed genetic superpowers.

In January, a team of researchers presented findings that suggest mutant wolves living in this toxic habitat are uniquely resilient to cancer-causing radiation exposure. 

And in May, scientists studying Eastern tree frogs with mutant black skin living near the site discovered that they live just as long as their green, non-mutant counterparts.

This could mean the exclusion zone is once again fit for human habitation. 

Kleiman hopes that his research, and future studies of the CEZ's stray canine populations, will help scientists understand the genetic effects of prolonged exposures to both radiation and non-radiation toxic exposures.

'Examining the genetic and health impacts of these chronic exposures in the dogs will strengthen our broader understanding of how these types of environmental hazards can impact humans and how best to mitigate health risks,' he said.