At the Chernobyl nuclear power plant in the north of Ukraine in 1986. In April, a disaster occurred that turned the surrounding area into the most radioactive zone on Earth. To this day, radiation levels remain high.
Animals living within a radius of 30 km around the power plant were found to be physically and genetically different from their relatives in other parts of the world. Researchers at New York University studied the microscopic worms that breed in this region to see how chronic radiation affects DNA.
“Chernobyl was a tragedy of unfathomable proportions, but we still don’t fully understand the impact this disaster had on local life,” said Sophia Tintori, lead author of the study. “Did a sudden change in environment result in the selection of species or even individuals of a species that are naturally more resistant to ionizing radiation?”
Scientists studied nematodes, tiny worms with simple genomes (an organism’s entire set of genetic material) and rapid reproduction that make them useful for understanding basic biological phenomena, undergoing tens of generations of evolution before a typical vertebrate “learns to tie its shoes.”
Hundreds of nematodes were collected from sites throughout the Chernobyl zone that had been exposed to varying levels of radiation. The samples are then transported to New York University, frozen and later tested.
“We can preserve the worms and thaw them later for research,” said researcher Matthew Rockman. “We stop evolution in the laboratory, which is not possible with most other animal models and is very valuable when we want to compare animals that have had different evolutionary histories.”
When researchers compared the genomes of nematodes from Chernobyl with worms from other locations, they found no radiation damage.
“This does not mean that Chernobyl is safe, it is more likely that nematodes are really resilient animals and can withstand extreme conditions,” Tintori said. “We also don’t know how long each of the worms we collected has been in the zone, so we can’t be sure what level of radiation exposure each of them and its ancestors has experienced over the past four decades.”
But the study’s findings provide insight into how DNA repair can vary between individuals, which may help to better understand the natural variation seen between people.
“Now that we know which nematode strains are more sensitive or tolerant to DNA damage, we can use them to study why different individuals are exposed to carcinogens more often than others,” said researcher S. Tintori.
This could have important implications for cancer research into why some people are genetically predisposed to the disease and others are not.
See pagan „New Atlas“ inf.
2024-09-01 11:01:09