Astronaut genes: Twins study reveals DNA secrets

Astronaut genes: Twins study reveals DNA secrets

Twin Power! How Astronaut Twins Helped Unlock Space DNA Secrets!

Imagine having an identical twin. Now imagine one of you going to space for a year, while the other stays on Earth! This incredible real-life experiment, known as the NASA Twins Study, gave scientists a unique chance to compare how space affects the human body down to our DNA, revealing amazing secrets about genetics and health in orbit.

The Perfect Match: Scott and Mark Kelly

The study involved identical twin astronauts Scott and Mark Kelly. Scott spent nearly a year (340 days) aboard the International Space Station (ISS), while his brother Mark stayed on Earth as a control. Because they share almost identical DNA, any differences scientists found in their bodies after Scott's mission could be more confidently linked to the effects of space travel, rather than individual genetic variations. It was the perfect natural experiment!

Beyond Genes: Epigenetic Changes

Scientists looked at almost every aspect of their health: their vision, bones, muscles, immune systems, and even their genes. One of the most fascinating findings was about "epigenetics." Epigenetics doesn't change your actual DNA code, but it changes how your genes are turned on or off. It's like having the same instruction manual but highlighting different parts or adding sticky notes. The study found changes in how Scott's genes were expressed in space, particularly those related to his immune system and DNA repair. They also looked at telomeres (the protective caps on DNA) and saw some interesting changes there, too.

Understanding Space: Learning for Earth

The Twins Study provided an unprecedented amount of data, showing that while many changes occurred in Scott's body, most returned to near pre-flight levels once he was back on Earth. This suggests the human body is remarkably resilient. The study's findings are vital for preparing for long-duration missions to Mars and beyond. By understanding how space affects us at a genetic and molecular level, scientists can develop better "countermeasures"—strategies and technologies to protect astronauts' health. And crucially, this research also provides insights into how the human body adapts to stress, aging, and disease, offering valuable lessons for health and medicine right here on Earth.

Key References:

• Garrett-Bakelman, F. E., & D. R. (2019). The NASA Twins Study: A Multiomics Portrait of a Year in Space. Science, 366(6461), 1-10. (The landmark primary publication of the NASA Twins Study findings).

• NASA Human Research Program (Twins Study): Provides accessible summaries, videos, and ongoing information about the study's results and implications.

• Bailey, S. M., Zhang, Y., & M. G. (2020). Telomere Length and Telomerase Activity in Response to Spaceflight in the NASA Twins Study. Science, 369(6505), 1162-1166. (A specific follow-up paper focusing on telomeres from the Twins Study).

• Biological and genomics journals: Publications in these fields have extensively analyzed and discussed the Twins Study data.