NASA Astronaut Who Spent A Year In Space Now Has Different DNA From His Twin

NASA Astronaut Who Spent A Year In Space Now Has Different DNA From His Twin

All living things have DNA in their cells.  DNA Chromosomes contain the genetic information that determines everything about us.  DNA controls the color of our hair, the color of our eyes, athletic ability and personality traits.  When a child is born genetic DNA material from both the mother and the father gets passed down to that child.   Heredity / genetics effects our health, as traits and health conditions can get passed down from parents to children.  Identical twins are twins who come from the same fertilized egg that splits and have the exact same DNA. 

2 astronaut brothers that are identical twins Scott and Mart Kelly were recently part of a DNA study that researched what happens to DNA in space.  Scott Kelly one of the twins has spent 500 days in space.  He was on a single mission on the International Space Station for 342 days.  NASA wanted to know how long term space travel affects the human body and our genes.  These astronaut twins gave NASA the opportunity to research this.

Space does change us on a DNA level!  Scott’s DNA did change.  Telomeres (the ends of chromosomes shorten as we age) were significantly longer in space.  These telomeres shortened after two days back on earth.  Most of the changes to Scott’s DNA returned to normal after being back on earth but he still shows a 7% change in DNA after two years.


Key Points:

  • 1Living in space does change us on a DNA level.
  • 2It is important to understand how space affects us and our ability to survive long space missions.
  • 3A manned trip to Mars could happen as soon as 2030.

A Mars mission would last as long as three years, which would obviously be the longest stretch that any human has been away from Earth. Can the human body handle such a journey?


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