NASA says twin astronauts DNA now different after space travel

NEW YORK -- You would expect a trip to space to be transformative, but NASA says it can lead to permanent DNA changes.

The space agency studied the DNA of twin astronauts Scott and Mark Kelly.

RELATED: Mark your calendars: The 'super blue blood moon' and more sky-watching events in 2018

Scott spent a year on the International Space Station while Mark remained on Earth.

Now two years later, NASA says 7 percent of Scott's DNA has changed, meaning the brothers are no longer identical.

Click here to read more from the NASA study.

Click here for a look at more stories about NASA.