Mark_and_Scott_Kelly_at_the_Johnson_Space_Center - Mark and Scott Kelly at the Johnson Space Center

Some of the changes to NASA astronaut Scott Kelly’s after returning from almost a year in space were easily apparent. In the absence of gravity, he grew a couple inches taller. He’s since shrunk back down.

But some of the changes happening to Scott weren’t so easy to see and researchers have been hard at work trying to learn what exactly space can do to one’s body at the cellular level. Because Scott has an identical twin brother and astronaut, Mark, those researchers got a unique opportunity to directly compare those changes against a control back here on Earth.

In their latest findings from the ongoing twins study, researchers observed an increase in methylation – the process of turning genes on and off. And they saw thousands of genes inside Scott’s body turning on and off “like fireworks” as soon as he entered space.

“Some of the most exciting things that we’ve seen from looking at gene expression in space is that we really see an explosion, like fireworks taking off, as soon as the human body gets into space,” Twins Study Principal Investigator Chris Mason, Ph.D., of Weill Cornell Medicine, said in a statement. “With this study, we’ve seen thousands and thousands of genes change how they are turned on and turned off. This happens as soon as an astronaut gets into space, and some of the activity persists temporarily upon return to Earth.”

Why is this important? We’re learning the human body has the ability to deal with the stresses of changing environments and disease through the process of gene expression. Our genes regulate the creation of proteins, which in turn build our cells and perform routine activities in the body. And we’re finding the body can turn specific genes on and off in order to better survive under changing circumstances. Take, for instance, changes to gene expression to help keep us alive when oxygen levels get too low.

These results indicate that going to space could have a profound impact on the way our cells function. And this impact can last for some time even after coming back to the familiar trappings of Earth. The findings could ultimately give huge insight into the risks to the human body associated with long-term space travel as well as into how we can protect against them.

NASA already teased us with some initial findings back in January with what they had learned of the twins up to that point. There, we mostly learned Scott’s telomeres – caps on our chromosomes that shorten over time as we age – had temporary gotten longer than his brother’s. NASA plans to publish their final results and findings on the twin study in a report coming 2018.

Kelly Paik
Kelly Paik writes about science and technology for Fanvive. When she's not catching up on the latest innovations, she uses her free-time painting and roaming to places with languages she can't speak. Because she rather enjoys fumbling through cities and picking things on the menu through a process of eeny meeny miny moe.