S.T.A.L.K.E.R. in real life: study shows Chornobyl dogs are evolving rapidly

The DNA of dogs living near the Chornobyl nuclear power plant is significantly different from the DNA of dogs living in the city of Chornobyl, Popular Mechanics reports, citing research by experts from the University of South Carolina and the National Human Genome Research Institute.

Scientists examined the DNA of 302 feral dogs living in the Chornobyl Exclusion Zone to better understand how radiation may have changed their genome. The results were published in the journal Science Advances.

"Do they have mutations that they’ve acquired that allow them to live and breed successfully in this region? What challenges do they face and how have they coped genetically?" said co-author Elaine Ostrander, an expert in canine genomics at the National Human Genome Research Institute, describing the aim of the study.

The idea that radiation accelerates natural evolution is not new. For example, the practice of deliberately irradiating seeds in space to induce desired mutations is now a well-established method for breeding crops that are well-suited to today's warming world.

Scientists have previously studied the DNA of certain animals living within the Chornobyl Zone, including bacteria, rodents, and birds. For example, a study conducted in 2016 showed that oriental tree frogs (Hyla orientalis), which usually have green skin, were more common in the Zone with black skin. Biologists suggest that the frogs had undergone a beneficial mutation in melanin, the pigment responsible for skin color, that helped to disperse and neutralize some of the surrounding radiation.

Back to dogs. A study has found that feral dogs living near the Chornobyl power plant show distinct genetic differences from dogs living just 10 miles (16 km) away in the town of Chornobyl. While this may seem like a strong hint that these dogs underwent some kind of rapid mutation or evolution due to radiation exposure, this study is only the first step in proving this hypothesis.

Such studies are always difficult, largely because mutations caused by radiation are difficult to distinguish from mutations due to other factors, such as inbreeding.

In any case, this study by experts from the University of South Carolina and the National Human Genome Research Institute provides a template for further studying the effects of radiation on large mammals, as the DNA of dogs living near the Chornobyl NPP and in Chornobyl can now be compared with the DNA of dogs living in non-irradiated areas.