Chernobyl’s stray dogs are genetically distinct, but radiation is not the cause

In 1986, the Chernobyl nuclear reactor was built in the Soviet Union, now located in Ukraine, explodedThis leads to the release of huge amounts of radioactive materials into the environment. Nearly four decades later, stray dogs roaming near the Chernobyl nuclear power plant are genetically different from those in the nearby city of Chernobyl, but perhaps not because of radiation.

Researchers from North Carolina State University (NC State) and Columbia University’s Mailman School of Public Health concluded that genetic differences between dogs in Chernobyl and those near the Chernobyl Nuclear Power Plant (NPP) were likely not driven by radiation-induced mutations. . Their research, detailed on December 27 He studies Published in the magazine One plusprovides insight into how catastrophic environmental pollution affects nearby residents over time.

“We worked with two groups of dogs that, even though they are only 16 kilometers apart, or about 10 miles, are genetically different,” said Matthew Breen of North Carolina State, who participated in the study, at a university. statement. “We are trying to determine whether low-level exposure over many years to environmental toxins such as radiation, lead, etc., can explain some of these differences.” in Previous genetic analysesBreen and his colleagues identified nearly 400 regions along the genome that represent differences between the two groups of dogs, some of which contain genes associated with DNA damage repair.

In the latest study, the team confirmed that the city’s dogs were genetically similar to dogs found in neighboring regions such as Russia and Poland, making them a representative control group to which the NPP group could be compared. They then looked for abnormalities and mutations in canine NPP that could have accumulated over time. Germline DNA mutations, for example, are heritable changes within the DNA of reproductive cells. The researchers began their analysis at the chromosomal level, then gradually focused on smaller and smaller genetic traits.

“Think of it like using the zoom function on your phone camera to get more detail — we start with a wide view of a subject and then zoom in,” Breen explained. “We know, for example, that exposure to high doses of radiation can lead to instability from the chromosomal level down. While this group of dogs is 30 or more generations removed from the group that existed during the 1986 disaster, it is likely that Mutations remain detectable if they confer a survival advantage to those original dogs but we found no such evidence in these dogs.

In other words, the researchers found no genetic mutations that could be caused by radiation exposure. However, it is still possible that evolutionary pressures from the nuclear reactor disaster led to the genetic difference between city dogs and NPP dogs.

“In human terms, this would be like studying a population centuries removed from the one that existed at the time of the disaster,” said Megan Dillon of NC State, who led the study. “It is likely that the dogs that survived long enough to reproduce already had genetic traits that increased their ability to survive. So there may have been intense selective pressure initially, and then the dogs at the power plant remained separate from the city population. Investigating this question is An important next step that we are working on now.

In fact, the harmful effects of the Chernobyl nuclear accident were not limited to radiation, said Columbia University’s Clayman, who also participated in the study. Toxins including heavy metals, lead powder, pesticides, and asbestos (a carcinogenic mineral) were released into the environment during the cleanup process. The broader impact of the nuclear disaster on nearby dog ​​populations provides important clues about how future pollution crises will impact human health.

“The importance of continuing to study the environmental health aspects of large-scale disasters such as this cannot be overemphasized,” Kleiman said. “It is certain that, given our increasingly technological and industrial societies, there will always be other disasters of this nature in the future.” We need to understand the potential health risks and how best to protect people.

It’s also comforting to know that the puppies wandering near the Chernobyl nuclear power plant have nothing to do with wild dogs Chernobyl Diary.