The International Space Station is one big research laboratory. Its earliest research objectives, back in 2000, were pretty straightforward: keep humans alive. Since then, the number of experiments conducted aboard the station has ballooned, and astronauts and cosmonauts spend their days studying how terrestrial science and technology works in microgravity. Over the years, the station’s residents have grown zucchini, beheaded flatworms, maneuvered humanoid robots, tended to mouse embryos, watched the muscles of zebrafish atrophy, and drawn their own blood, using their own bodies as test subjects. Scrolling through NASA’s full list of experiments, one gets the sense that almost any experiment that can be done in a lab on Earth can be replicated in one floating 200 miles above.
So it shouldn’t be too surprising that humans have successfully sequenced DNA in space.
Last summer, NASA dispatched Kate Rubins, a microbiologist with a doctorate in cancer biology, to try it for the first time. Rubins has spent her career studying infectious diseases and worked with the U.S. Army to develop therapies for the Ebola and Lassa viruses. She has sequenced the DNA of different organisms plenty of times on the ground, but the process was a little bit more nerve-wracking on the space station. “I didn’t want to screw it up,” she says.
I spoke to Rubins during her recent visit to NASA headquarters in Washington, D.C. about the experiments she worked on during her four-month stint on the ISS. Our conversation, edited for length and clarity, is below.
But first, a brief rundown of how DNA sequencing actually works. Rubins used a specially made biomolecule sequencing device, a miniature version of the microwave-sized hardware on Earth. DNA samples are fed into its protein nanopores, tiny structures embedded in a synthetic cell membrane. The device sends an ion current through this membrane. When the bases of DNA—guanine, adenine, thymine, and…