DNA Blasts Off!

In space, astronauts experience microgravity—gravity much weaker than that on Earth. They might also be exposed to higher levels of radiation—high-energy particles or rays—since they’re no longer protected by Earth’s atmosphere. And they have to endure a stressful spaceflight. All of these things may affect astronauts’ health (see Earth Twin, Space Twin).

“When I was younger, I learned that astronauts get sick a lot when they go to space, much more often than the average person on Earth,” says Anna-Sophia. “Their immune system [which fights infections] gets weaker.”

In space, astronauts experience microgravity. It’s much weaker than gravity on Earth. They might also be exposed to higher levels of radiation. That’s because Earth’s atmosphere isn’t protecting them from these high-energy particles and rays. And they have to go through a stressful spaceflight. All these things may affect their health (see Earth Twin, Space Twin).

“When I was younger, I learned that astronauts get sick a lot when they go to space, much more often than the average person on Earth,” says Anna-Sophia. “Their immune system [which fights infections] gets weaker.”

Anna-Sophia began learning about space and the human body. She started by reading her biology textbook, speaking with her teacher at Fox Lane High School in Bedford, New York, and studying articles in scientific journals. 

Anna-Sophia learned that spaceflight causes many changes in a person’s DNA. In humans and other organisms, DNA molecules carry genes—units of hereditary information (see Structure of DNA). From her research, Anna-Sophia found that one way the environment can affect a person’s health is through subtle epigenetic changes to DNA. These changes happen when diet, stress, toxic substances, and other environmental factors cause small chemical markers to be added to or removed from DNA. They can affect many biological processes in the body, including how the immune system functions. 

Anna-Sophia began learning about space and the human body. She started by reading her biology textbook and speaking with her teacher at Fox Lane High School in Bedford, New York. She also studied articles in scientific journals. 

Anna-Sophia learned that spaceflight causes many changes in a person’s DNA. In humans and other living things, DNA molecules carry genes. These are units of hereditary information (see Structure of DNA). From her research, Anna-Sophia found one way the environment can affect a person’s health. It’s through tiny epigenetic changes to DNA. Diet, stress, toxic substances, and other factors in the environment can trigger these changes. These factors cause small chemical markers to be added to or removed from DNA. The changes can affect many of the body’s processes. They even affect how the immune system works. 

The Genes in Space contest asked entrants to come up with an experiment using one of the ISS’s new instruments, a miniPCR machine. The device makes millions of copies of small chunks of DNA to help scientists study this important molecule. 

When Anna-Sophia learned that the miniPCR machine could be used to detect epigenetic changes, her project idea was born. Working with her mentor, biology graduate student Holly Christensen of the Massachusetts Institute of Technology, Anna-Sophia developed two identical procedures—one to be carried out on Earth and one on the ISS. The goal was to find out if the miniPCR machine would work the same way on Earth as in space. “We don’t know for sure because it’s never been used in space,” she says.

The Genes in Space contest asked for experiments that use the ISS’s new miniPCR machine. This instrument makes millions of copies of small chunks of DNA. The copies help scientists study this important molecule.

Anna-Sophia learned that the miniPCR machine could help detect epigenetic changes. That’s when her project idea was born. She worked with her mentor, biology graduate student Holly Christensen of the Massachusetts Institute of Technology. Anna-Sophia came up with two procedures that were exactly the same. One would be carried out on Earth and one on the ISS. She wanted to find out if the miniPCR machine would work the same way on Earth as in space. “We don’t know for sure because it’s never been used in space,” she says.

Once Anna-Sophia’s proposal was selected as the winner of the Genes in Space contest, she took samples of DNA from baby zebrafish. “I prepared two identical sets of DNA samples,” she says. “One set was to be sent into space with the miniPCR machine, and the other was to be kept on Earth with an identical miniPCR machine,” she says. The samples left on Earth would act as a control—a constant against which she could compare the results of her space experiment.

Anna-Sophia chose zebrafish DNA for her experiment because when zebrafish are young, they go through known epigenetic changes. Anna-Sophia could look for these markers and use them as a standard, or established reference, to verify that the miniPCR in space was working as it does on Earth. 

After Anna-Sophia’s idea won the Genes in Space contest, she took DNA samples from baby zebrafish. “I prepared two identical sets of DNA samples,” she says. “One set was to be sent into space with the miniPCR machine, and the other was to be kept on Earth with an identical miniPCR machine.” The samples left on Earth would be the control—something that doesn’t change. She could compare the results of her space experiment with the control. That way, she’d know if the results were different in space.

Anna-Sophia chose zebrafish because scientists know that the young fish go through certain epigenetic changes. Anna-Sophia could look for these markers. She could use them as a standard, a reference that has been set. This would tell her if the miniPCR in space was working the same way as on Earth. 

In April, a SpaceX rocket carried the space-bound portion of the experiment from Kennedy Space Center in Titusville, Florida, to the ISS. Anna-Sophia attended the launch. “It was surreal to watch,” she says. “I almost couldn’t believe it was happening.”

In April, a SpaceX rocket traveled from Kennedy Space Center in Florida to the ISS. It carried the part of the experiment that would be done in space. Anna-Sophia was at the launch. “It was surreal to watch,” she says. “I almost couldn’t believe it was happening.”

After the experiment reached the ISS, British astronaut Tim Peake placed Anna-Sophia’s samples in the miniPCR machine and turned it on. It was the first time anyone had made copies of small chunks of DNA in space. “Both sets of samples—on Earth and in space—were put through the exact same protocol [or set of steps],” says Anna-Sophia. In May, Peake sent the samples back to Earth in a spacecraft that landed safely in the Pacific Ocean, and a ship set out to retrieve it. “On behalf of all of us involved in human spaceflight, we thank you for your contributions,” said Peake in a video message to Anna-Sophia from the ISS.

On the ISS, British astronaut Tim Peake placed Anna-Sophia’s samples in the miniPCR machine and turned it on. It was the first time anyone had made copies of small chunks of DNA in space. “Both sets of samples—on Earth and in space—were put through the exact same protocol [or set of steps],” says Anna-Sophia. In May, Peake sent the samples back to Earth. The spacecraft carrying them landed in the Pacific Ocean, and a ship set out to meet it. Peake sent a video message from the ISS. “On behalf of all of us involved in human spaceflight, we thank you for your contributions,” he told Anna-Sophia.

After the samples returned from space, Anna-Sophia analyzed and compared them with the ones that had remained on Earth. Just as she had hoped, they looked identical. The results confirmed that the miniPCR machine really does work in space. “Now, hopefully, we can use it to look for changes to astronauts’ DNA that might affect their health.”

Anna-Sophia studied the samples that had returned from space. She compared them with the ones that had stayed on Earth. They looked the same, just as she had hoped. The results showed that the miniPCR machine really does work in space. She says, “Now, hopefully, we can use it to look for changes to astronauts’ DNA that might affect their health.”