NASA’s ground-breaking Twins Study has revealed that space travel causes an increase in DNA Methylation, the process by which genes are turned on and off.
The unique research project saw NASA astronaut Scott Kelly spending a year on the International Space Station while his twin brother Mark Kelly, a retired NASA astronaut, stayed on Earth to act as a control. The results of the study will pave the way for future missions to Mars by helping us to understand how long-duration space travel affects the human body.
Ever since Scott Kelly returned from his 340-day stay on the ISS, NASA researchers have been collecting and analysing samples from the two brothers looking for correlations. "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,” said Twins Study Principal Investigator Chris Mason.
“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.”
Kelly’s stay on the space station also formed the basis of the ‘One Year Mission’ in which he and Russian Cosmonaut Mikhail Kornienko stayed on the ISS for nearly 12 months. Most astronauts only stay on the ISS for a maximum of six months.
Last year, it was revealed that Scott Kelly had gained two inches in height during his stay on board the orbiting laboratory, thanks to the micro-gravity environment.
Researchers will also be paying close attention to changes in Kelly’s eyesight - a common result of long missions in space. Last year, a study concluded that eyesight trouble in astronauts is down to cerebrospinal fluid (CSF), which usually cushions the brain and spinal cord. While CSF is used to adapting to different body positions, is gets confused by the lack of posture-related pressure changes caused by floating around in zero gravity.
Retired Astronaut Scott Kelly Reflects on Year-Long ISS Mission
The journey to Mars will take around 30 months so a clear understanding of what such a long stay in space could do to the body is vital so that experts can come up with ways to prevent or deal with the changes. The Twins Study is investigating the short- and long-term effects of microgravity and space radiation, along with the mental ramifications of being cooped up in a spacecraft for so long.
“This study represents one of the most comprehensive views of human biology,” Mason said. “It really sets the bedrock for understanding molecular risks for space travel as well as ways to potentially protect and fix those genetic changes.”
The full results of the Twins Study are due to be published in 2018.