Astronaut’s DNA no longer matches identical twin’s after time in space, NASA finds

NEW YORK — We all know spending a year in outer space would likely change your outlook but a new study suggests it could also change your genes.

NASA has learned astronaut Scott Kelly and his identical twin, astronaut Mark Kelly, are no longer genetically the same.

This is after Scott spent a year aboard the International Space Station as part of NASA’s groundbreaking twin study.

According to researchers, seven percent of Scott's genes did not return to normal after his return to earth two years ago.

“That’s not that surprising because your genes express themselves differently all the time,” Rachel Feltman, Science Editor for Popular Science told PIX11 News.

According to Feltman, while the headline of “DNA space mutation” may seem thrilling, you have to consider all the facts.

Let’s break it down: this is a telomere – it’s the cap at the end of your chromosomes. Feltman explains the rest.

“Based on what we understand, as you age it’s because your telomere’s are getting shorter,” Feltman said. “[Kelly’s] got longer in space which sounds kind of surprising, it’s like he aged backwards.”

“Actually we already know that your telomeres get longer when you live a healthy lifestyle.”

Scott, like all astronauts in space,  has an incredibly healthy lifestyle, which sheds light on that “telomere growth.”

Researchers maintain the study is relevant as it will help them understand what happens to the human body – and what doesn’t – before sending more astronauts on longer missions. ​