Scientists Discuss Findings from NASA’s Twin Study
Last Friday researchers announced that almost one year in space changed astronaut Scott Kelly’s immune system, as well as the activity of some of his genes when compared to his identical twin who stayed on Earth
Although, scientists couldn’t tell if the changes were good or bad the results from this one-of-a-kind NASA twin study is raising new questions for doctors as NASA plans to fly humans to Mars. By testing these genetic doubles, scientists had a once in a lifetime chance to monitor details of human biology, including how an astronaut’s genes turn on and off in space differently than when they’re back on Earth. One mystifying change that the scientists discussed on last Friday at a science conference was how Kelly’s immune system became hyperactivated.
Christopher Mason, a geneticist at Weill Cornell Medicine in New York explained that it’s as if his body was reacting to the alien environment almost the same as one would with a strange organism living inside you. Mason, who helped lead the study said doctors are currently looking for signs of that in other astronauts.
NASA has been examining the effects of space exploration on an astronaut’s body since the beginning. However, most astronauts are in space for approximately six months while Kelly lived aboard the International Space Station for 340 days, setting a US record.
Kelly, who is now retired said in an email to The Associated Press that he never felt entirely normal when he was in space. He noted the typical symptoms such as congestion from moving fluid, headaches, and difficulty concentrating due to extra carbon dioxide, as well as digestive issues due to a lack of gravity.
However, the twin study was a particular dive into the molecular level since they had former astronaut Mark Kelly, Scott’s twin, down on Earth for comparison. They have yet to publish the full results, but researchers discussed some of the findings on Friday in a meeting of the American Association for the Advancement of Science.
Several genes linked to the immune system became hyperactive, according to Mason. It was not a change in DNA but a change in what’s known as gene expression, which is how genes turn on and off and increase or decrease the number of proteins they produce. Mason also identified a spike in the bloodstream of another marker that helps prepare the immune system.
Nevertheless, at the same time, Kelly’s blood showed less of another cell type, which is known to be an early defence against viruses.
It’s not surprising that gene activity changes in space because it changes in response to many different types of stress.
The good news is that almost everything was back to normal shortly after Kelly returned to Earth in March 2016. However, the genes related to the immune-system appeared to have this memory or this need to be almost on high alert even six months after, according to Mason.
Craig Kundrot, who is in charge of space life and science research for NASA said that overall it’s encouraging because there are no significant new warning signs. They see changes that they didn’t necessarily expect, but they still aren’t sure if those changes matter.
The twin study has given NASA various things to look out for on future missions to find out if other astronauts react in the same way. On future missions, astronauts can perform some of this testing in space rather than freezing samples to send back to scientists on Earth, said Mason.
A crewed mission to Mars, which NASA hopes to deploy in the 2030s, would take nearly three years, including time on the surface, according to Kundrot.
One of the main concerns about this mission is radiation. The mission would expose astronauts to cosmic radiation levels that are higher than NASA’s own safety standards but not by too much over the standard.
On our planet and even on the ISS, Earth’s magnetic field protects astronauts from the majority of radiation. However, there would be no such protection en route to Mars and back, but Kundrot said that once on Mars tunnels or dirt-covered habitats could help.
Kelly, who will be 55 next week, said he’d take the trip to Mars because it wouldn’t be worse than what he already went through. Possibly better.
Photo credit: NASA
