NASA clarified that the news reports about astronaut twin Scott Kelly’s DNA being altered after spending one year in space are not entirely accurate. The space agency noted that its twin study has been misinterpreted by the mainstream media.
Last Thursday, dozens of headlines suggested that Kelly’s stay in space led to changes to his DNA and he was no longer an identical twin to his brother, Mark, who remained on Earth.
People’s magazine wrote: “Astronaut Scott Kelly’s DNA No Longer Matches Identical Twin’s”
USA Today: “NASA and Scott Kelly: Space travel changes DNA”
The Independent: “Astronaut’s DNA changes after spending year in space” (the story has been since deleted)
NASA insisted that Kelly’s DNA was not altered “fundamentally”. The U.S. space agency explained that only his gene expression changed after one year in space. Gene expression mirrors the body’s reaction to changes in the environment. Gene expression changes are not permanent, as those stories suggested.
Scott Kelly’s Reaction
Scott said on Twitter that he had no idea that his DNA changed after nearly one year in space. He even joked about not having to call Mark his identical twin anymore.
What? My DNA changed by 7%! Who knew? I just learned about it in this article. This could be good news! I no longer have to call @ShuttleCDRKelly my identical twin brother anymore. https://t.co/6idMFtu7l5
— Scott Kelly (@StationCDRKelly) March 10, 2018
The false media reports were based on a NASA report, but the media got it all wrong. Many news agencies took too seriously a phrase in the NASA report about Kelly’s “space genes” (around 7% of his genes’ expression) not returning to normal upon his arrival to Earth.
NASA insisted that the two veteran astronauts remain identical twins and that the astronaut’s DNA has not mutated fundamentally in space. The changes affected only his gene expression, not Kelly’s DNA.
Gene expression can change even on Earth if the person is under a lot of physical stress like it usually happens during SCUBA diving or mountain climbing activities. NASA promised to offer more details about its twin study this summer.
Image Source: NASA