This question is of increasing importance, especially as multiple groups make plans to send humans to Mars. Aside from the time and fuel needed to make these kinds of long trips, there’s currently no safe way to make sure colonists can survive the trip, let alone prolonged stay on the Red Planet. As such, scientists are now turning to genetics for answers; specifically, genetic modifications.
Let’s arrest your thought process right away: no, scientists are not considering growing astronauts from stem cells or cloning them in any way. Instead, they’re looking at ways we could modify the genetic makeup of astronauts in a lab, so they can be better suited to the hazards in deep space. For instance, can astronauts’ genes be shuffled to make them resistant to the constant bombardment from cosmic radiation? What about making them able to naturally produce the vitamins their body needs?
Building the perfect astronaut
Christopher Mason, a member of the Department of Physiology and Biophysics at Weill Cornell Medicine, is one researcher attempting to answer these questions. In 2011, he suggested a “500-year plan” to get humans off Earth, a large portion of which involves genetic modification. “I think we have to consider it for people that we send to other planets,” he says. “We don’t know if it’s a slight nudge to existing gene expression, or a whole new chromosome, or finally a complete rewriting of the genetic code.”
According to Mason, scientists have at least another 10 years of work ahead of them before they can really understand the effect of extended space travel on your genes. His lab was also selected to be a part of a special NASA study involving twin astronauts Scott and Mark Kelly. Ever since Scott came back from a year on board the International Space Station, Mason has been studying the physiological differences between the two. It’s the closest NASA has gotten to any research involving tailoring astronauts to suit space travel.
Man’s real best friend, Ctrl+V
In fact, Mason says his lab is already on the precipice of a major breakthrough in their research. The team has been studying how to make human cells radiation-proof, to protect astronauts from cosmic background radiation, using copies of the p53 gene. Called the “protector of the genome”, this gene is present in excess in elephants, which may be related to the number of cancer cases in the animal being much fewer than other species. The team has been adding extra copies of this gene to human cells in labs, in order to test the theory, and may soon even be sending their modified cells to the space station to test.
Thanks to the evolution of CRISPR technology, which allows geneticists to make subtle changes to a genome, this sort of genetic editing has become even easier to test in labs. It’s the first step to a future where humans could (if not against the law at the time) genetically modify their babies even before they’re born. While the research into the technology has been geared towards fighting hereditary diseases by essentially “deleting” them from the host’s DNA, it could also hold answers for the future of space travel.
How much is too much?
However, this is a razor-sharp knife edge for geneticists to walk. How much gene editing can you support before it becomes unethical to make changes? What body should supervise this kind of work, and who should be on the panel? Should it only be restricted to fighting diseases and deformities or is it also okay to correct smaller flaws like sub-par eyesight or make a child smarter?
Mason’s research comes into play especially when considering colonies on alien planets. Right now, the push is to design habitation spaces, suits, and spacecraft that could make the astronauts’ environment as close to home as possible. What if, instead, we could change our astronauts so they could survive wherever they’re going instead, without needing additional support resources?
The astronaut cook book
A few scientists are already considering what genes would be best to help in that situation. If we could gather genes found in people in different environments – ones from people living at altitudes that would let you survive with at lower oxygen levels, or leaner muscles to stave of atrophy from prolonged spaceflight or low gravity habitation, or perhaps even an increased fertility gene to speed up population growth when sending a small team to colonise a planet. Gather them all into one astronaut and you have the perfect person to travel to space, tailor-made, instead of testing hundreds and thousands of regular individuals to see if they at least have one or two of those genes.
That’s where the future is headed; we just have to hope that the renewed space race doesn’t push the researchers involved past their ethical boundaries.