A population of feral dogs living near the Chernobyl Exclusion Zone has now given scientists a glimpse into the multigenerational effects of radiation exposure. The radiation, which is still prevalent in Chernobyl decades after the nuclear disaster of 1986, could have fundamentally changed the genetics of the dogs there, as a study shows.
Interesting for the researchers: The changes in genetics also differ between the different dog packs, since they were exposed to different levels of radiation. The animals that still live in the exclusion zone are probably descendants of domestic animals. These were left behind when residents around the Chernobyl power plant fled in a hurry in 1986, leaving all their belongings behind, Tim Mousseau, a professor at the University of South Carolina, told ABC News.
Between 2017 and 2019, the researchers took blood samples from more than 300 dogs from the region, which were collected between 2017 and 2019 at sites with different levels of contamination. While the construction of a new facility for the failed nuclear reactor began on site, volunteers took care of sterilizing the wild dogs and giving them medical care - they also took blood samples right away.
Many of the diseases in the dogs were previously observed in human survivors of the atomic bombing of Japan during World War II. For example, they are more likely to suffer from cataracts (an eye disease): according to Tim Mousseau, sensitive eyes are the first organs to show signs of prolonged exposure to nuclear radiation.
In their study, the researchers differentiate between different dog populations: The dogs in the town of Chernobyl have a boxer and rottweiler background, while the dogs in the nearby town of Slavutych have more Labrador retrievers in them, according to Ostrander. Large genetic variations within and between geographic locations in the Chernobyl Exclusion Zone suggest the dogs live close together, move between locations and breed freely, the study shows.
Apparently, the animals were also able to survive by hunting wild animals. Although the radioactive contamination destroyed large parts of the wild population in the region, some animals survived and continued to reproduce. So there was enough food for domestic dogs to survive by hunting, they went wild and continued to reproduce.
The researchers are now in the process of determining the dogs' genetic development over the most recent generations and studying how they have survived and reproduced during this time. The scientists are also looking for other developmental anomalies such as tumors or smaller brains. However, detailed results are still pending.
Quellen: "ABC News", "Science Advances"