Chris Mason has never met Scott Kelly, but he knows all about his DNA.
Mason, a geneticist at Weill Cornell Medicine in New York City, is one of the researchers participating in NASA’s twins study, an investigation of the effects of space travel on the human body. In 2015, Scott launched to the International Space Station for a 340-day stay while his identical brother Mark Kelly, also an astronaut, went about his life on Earth. For months, the brothers rolled up their sleeves for regular blood draws. Some samples beat Scott back to Earth, hitching a ride with other astronauts on their return trip on the Russian Soyuz.
“I’d go to bed at night and check Twitter and see he’d posted another amazing, beautiful view of Earth from space, and was smiling thinking of his DNA comfortably and securely sitting in my freezer,” Mason said.
The Kellys actually came up with the idea for a study themselves, pointing out to NASA that, hey, they’re identical twins, and maybe there’s some science to be done when one is on a planet and the other’s not. The space agency agreed and put out a call for research proposals. In 2014, NASA picked 10 teams and gave them a combined $1.5 million over three years. Scott returned last March, and researchers have been pouring over the samples since, looking for evidence of genetic changes in Scott that potentially could be attributed to living and working in the extreme environment of space.