Astronaut Scott Kelly spent 11 months aboard the ISS. A study, involving his twin brother, shows that this sojourn in space altered his DNA.
The results recently released by NASA should be of particular interest to Thomas Pesquet, the French astronaut currently on a mission aboard the International Space Station (ISS). The American space agency indeed presented, during a congress in Galveston (United States), the first analyzes of the data collected during the mission of the American Scott Kelly. And it seems that stays in orbit around the Earth are not without effect on DNA.
Space medicine did not wait until 2017 to examine the changes induced by space flights and stays. But if these results arouse so much interest, it is because they are the first, in this field of research, obtained on twins!
Isolate the effects of the environment
Scott Kelly is one of the most traveled astronauts: 520 days in total, including 340 consecutive in 2015-2016. And Scott also has the distinction of having a twin brother, Mark, also an astronaut for NASA, who only spent 54 days in flight.
Twins have always fascinated researchers and doctors. To be able to study human beings in all identical points, down to the smallest bases of their DNA, is indeed more than precious. The work carried out on twins thus provides a better understanding of the effects of the environment on the human organism.
“They both went through the same medical testing program before, during and after the mission. This will allow very fine comparisons to be made in order to discern more clearly which biological modifications are due to weightlessness, and those which are simply the result of aging and the passage of time ”, explained to Why actor, French astronaut Jean-François Clervoy.
Jean-Francois Clervoy, astronaut: ” It was a perfect opportunity to compare (…) Having Mark as a comparison on the ground is very interesting. ”
Recording of March 12, 2015
Surprising observations
The researchers were particularly interested in the possible modifications induced on Scott Kelly’s DNA by his stay in the ISS. Since astronauts are subjected to significant radiation during space flights, scientists expected to observe damage to Scott Kelly’s genetic material. However, they found that his telomeres had actually lengthened compared to those of his brother. “This is exactly the opposite of what we expected! Said Susan Bailey, radiation biologist at Colorado State University. Indeed, the length of these zones, located at the ends of chromosomes, is known to decrease during aging.
These results were so surprising that the researchers asked a second laboratory to redo the analyzes. They confirmed the first ones. Would stays in space therefore have the virtues of a makeover? A question that researchers are still far from being able to answer. These are only preliminary results, they were careful to point out during their presentation.
A publication still uncertain
Scott Kelly’s telomeres returned to their original length quite quickly after returning to Earth. A result that the researchers have there too, still a little difficult to interpret. A study, launched in parallel on ten other astronauts, should quickly help them see more clearly, specifies the review Nature. The results are expected in 2018.
As for the data of the Kelly brothers, we will have to be patient before seeing them published, have already warned NASA researchers. It is also possible that some of this information will never be revealed. Given their very personal character and the lack of complete anonymity of the data, Scott and Mark Kelly were granted the right to be able to proofread the works before publication, and possibly to keep the data public.
.
