Behind him Chernobyl nuclear plant accidentthe areas close to the plant continue to be dangerous for humans. He reactor number four The Vladimir Ilyich Lenin plant exploded on April 26, 1986, releasing 500 times more radioactive material in northern Ukraine than was used in the Hiroshima bomb. It was a natural disaster that, little by little, became a paradise full of radioactive animals and plants.
And it is because, beyond the few humans who work in maintenance tasks, the visits and those who installed the New Safe Sarcophagusthe animals roam freely. Among them, there are dogs, so many that they were baptized as “the Chernobyl puppies”. When the accident occurred, the dogs were abandoned, but in recent years, the population has skyrocketed and it is estimated that there are around a thousand dogs roaming freely.
Petting one of these adorable little dogs is not a good idea due to their radioactive load, but a new study points out that the genetic differences of these dogs have nothing to do with a radiation-induced mutation.
The radioactive dogs of Chernobyl
Watching the video above, it seems impossible to resist the temptation of petting these puppies. The problem is that they have radioactive particles in their fur, but the incredible thing about this story is that they simply exist so close to the accident zone.
The ionizing radiation It interacts in a curious way with the tissues of living beings: it breaks chemical bonds and modifies the structure of the chains of atoms. It is what causes animals to develop tumors, something that The plants adapted much better due to its particularities.
Of that thousand of dogs wandering around Chernobyl302 have been under study for some time by the University of South Carolina or the National Human Genome Research Institute with the purpose of characterizing their genetic structure. The animals belong to three different populations that have lived inside the plant and at distances of between 10 and 15 kilometers from ‘ground zero’.
Their research aims to help answer questions about how humans and other species can adapt to survive in such aggressive environments, and researchers are already getting some answers. The first thing is that it seems that these dogs are evolving at a different rate than dogs from neighboring areas.
They have some distinctive genetic traits in their DNA that they have developed over the years and a few months ago they already they dropped that the radiation could have nothing to do with them. Now it is North Carolina State University and the Mailman School of Public Health at Columbia University who have shared a study in which they claim that they have been working with two populations of dogs, separated only by about 16 kilometershave different genetic traits.
“We are trying to determine whether exposure to low levels of environmental toxins, such as radiation, lead, etc., over many years could explain some of these differences,” says Matthew Breen, one of the authors. What they did was start looking for differences at the chromosomal level, later in small intervals of the genome and, finally, differences in nucleotides.
Reactor number 4 with its current sarcophagus
The goal was to find abnormalities and evidence of DNA mutations in reproductive cells, which are passed from generation to generation. “It’s like using the zoom function on your phone’s camera to get more details: We start with a wide view of the subject and then zoom in,” says Breen. And the result is interesting, since it seems that radiation does not have much to do with the changes found:
“We know that, for example, exposure to high doses of radiation can introduce instability from the chromosomal level down. Although this dog population is 30 or more generations removed from those present during the 1986 disaster, the mutations would likely still be detectable if they offered a survival advantage to those original dogs. But we found no evidence of that in these dogs.”
The work follows its coursesince with what they have found, the researchers cannot rule out the role of selective pressure in explaining the differences between the two populations of dogs.
“In human terms, this is like studying a population that is centuries away from the one that was present at the time of the disaster. It is possible that the dogs that survived long enough to reproduce already had genetic traits that increased their ability to survive and, perhaps, what there was was extreme ‘natural selection’ at the beginning,” says another of the authors, Megan Dillon.
The researcher points out that it may be that, after this extreme pressure, the nuclear plant dogs were simply kept separate from the city’s population. “Investigating this path is a next step that we are working on,” he comments.
Unavoidable disasters
Another of the authors is Norman Kleiman, of the Columbia University School of Public Health. Keiman comments that “most people think of the Chernobyl nuclear accident as a radiological disaster in an abandoned corner of Ukraine, but the potential adverse health implications are much broader,” and this is due to many other toxins, such as heavy metals, lead dust, pesticides and asbestos.
The curious thing is that most of these toxins were released into the environment during the decades of cleanup that followed and this is something that may also have had an influence on the living beings in the area. “Studying companion animals, like these dogs, gives us a window into the types of health risks that people may face.”
“The importance of continuing to study the environmental health aspects of large-scale disasters like this cannot be overstated. It is certain that, given the increasingly technological and industrial nature of our societies, there will inevitably be other similar disasters in the future, and we need to understand the possible health risks and how to better protect people,” the researcher emphasizes.
Thus, understanding these genetic variations in dogs is not only the answer to a scientific curiosity, but also something practical in order to better understand the natural risks of certain particles in the face of another possible, according to Kleiman, disaster of similar dimensions.
Images | Cloth Map, Tim Porter
