Genetically engineered humans could be the future of space travel

 

When considering human settlements on the Moon, Mars, and beyond, much consideration is given to travel times, food, and radiation risk.

We will undoubtedly face a hostile environment in deep space, and some thinkers have discussed genome editing as a way to ensure that humans can tolerate these harsh conditions when they venture further into the solar system.

In January, I was lucky enough to attend a much-anticipated debate between Astronomer Royal Lord Martin Rees and Mars exploration advocate Dr Robert Zubrin. The event, held at the British Interplanetary Society, focused on whether Mars exploration should be human or robotic.

In a recent book, The End of Astronauts, Lord Rees and his co-author Donald Goldsmith outline the benefits of exploring the solar system using robotic spacecraft and vehicles, without the expense and risk of sending humans to explore. Dr Zubrin supports human exploration.

There was some consensus on Rees’ recommendation to use gene-editing technology to enable humans to overcome the immense challenges of becoming an interplanetary species.

Our genome is the entire DNA present in our cells. Since 2011, we have been able to modify genomes easily and precisely. This is how a molecular tool called Crispr-Cas9 was born, which can now be used in a high school laboratory at a very low cost and has even been used aboard the International Space Station.

Then came techniques called base editing and core editing, through which tiny changes can be made to the genome of any living organism.

The potential applications of gene editing to allow us to travel further are almost limitless. One of the most problematic hazards astronauts will face in deep space is a higher dose of radiation, which can disrupt many processes in the body and increase the risk of cancer in the long term.

Perhaps using genome editing, we could insert into humans genes from plants and bacteria that can clean up radiation from radioactive waste spills and nuclear fallout.

It sounds like science fiction, but leading thinkers such as Lord Rees believe it is the key to our progress across the solar system.

Identifying and inserting genes into humans that slow aging and combat cellular degradation could also help.

We could also engineer crops that are resistant to the effects of radioactivity exposure, since crews will have to grow their own food. We could also customize medications to the needs of astronauts, based on their unique genetic makeup.

Imagine a future where the human genome is so well understood that it becomes malleable in the face of this new personalized medicine.

Kate Rubins

Kate Rubins was the first person to sequence DNA in space.(NASA)

The genes of extremes

Tardigrades are microscopic animals sometimes called “water bears.” Experiments have shown that these tiny creatures can withstand extreme temperatures and pressures, high radiation, and starvation. They can even survive the vacuum of space.

Geneticists are keen to understand their genomes, and a paper published in Nature sought to uncover the key genes and proteins that give the miniature creatures this extraordinary tolerance to stress.

If we could insert some of the genes involved into crops, could we make them tolerant of the highest levels of radiation and environmental stress? It’s worth exploring this possibility.

Even more interesting is whether inserting tardigrade genes into our own genome could make us more resistant to the harsh conditions of space. Scientists have already shown that human cells in the laboratory developed increased tolerance to X-rays when tardigrade genes were inserted into them.

Gene transfer from tardigrades is just one speculative example of how we might engineer humans and cultures more suited to space travel.

Much more research will be needed for scientists to get to that point. However, in the past, several governments have been keen to impose strict restrictions on how genome editing is used, as well as on other technologies that insert genes from one species into another.

Germany and Canada are among the most cautious countries, but elsewhere restrictions appear to be easing.

In November 2018, Chinese scientist He Jiankui announced that he had created the first genetically modified babies. He inserted a gene into the unborn twins that gave them resistance to HIV infection.

The scientist was later imprisoned, but has since been released and allowed to continue his research.

In the new space race, some countries could go so far as to engage in genome editing, something others, especially in the West where restrictions are already strict, could not do. The winner would reap enormous scientific and economic benefits.

If Rees and other futurists are right, this field has the potential to advance our expansion into the cosmos. But it will take society to accept it.

There is likely to be opposition, due to deep-seated fears of altering the human species forever. And since base editing and prime editing have now improved the precision of targeted gene editing, it is clear that the technology is moving faster than the debate.

It is likely that some country will take the plunge where others have turned away. Only then will we know to what extent these ideas are really viable.

So far we can only speculate with curiosity, and perhaps also with enthusiasm.The conversation

Sam McKee, Associate Tutor and PhD Candidate in Philosophy of Science, Manchester Metropolitan University

This article is republished from The Conversation under a Creative Commons license. Read the original article.