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A geneticist proposes a radical plan to help humanity live comfortably on other planets

The Next 500 Years: Engineering Life to Reach New Worlds

Christopher E. Mason
MIT Press
296 pp.
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Humans have the capacity for very long-term thinking, yet we are often careless about the welfare of Earth and reckless when it comes to our destructive abilities. As such, we may eventually be confronted with the necessity of colonizing the Universe. In such a scenario, might it be possible to genetically modify humanity to optimize ourselves for the new environmental challenges we will face on other planets? In his new book, The Next 500 Years, geneticist Christopher Mason argues, “It is no longer a question of ‘if’ we can engineer life—only ‘how’” and that “Engineering is humanity’s innate duty, needed to ensure the survival of life.”

In the book’s first chapter, Mason discusses his role in the NASA Twins Study (1), which sought to measure various physiological markers in astronaut Scott Kelly during a year aboard the International Space Station and compare these indices with comparable data from his identical twin, astronaut Mark Kelly, who remained earthbound during the same period. The study, he argues, which found (among other things) that the expression of a number of genes related to DNA repair remained elevated 6 months after Scott returned to Earth, has enormous implications for understanding exactly how the space environment affects the human body.

Mason begins the next chapter by expressing an almost messianic belief in what he sees as the uniquely human responsibility of preserving life, not only our own but that of all of the other species in the Universe. He fails to consider, however, numerous ethical and logical possibilities, including, for example, our obligations to future humans as well as the potential cost of attempting to preserve life above all other considerations.

Over the next 10 chapters, Mason discusses the peculiarities, challenges, and targets of each of the 10 phases into which he divides his proposed space colonization project. The first phase, already completed between 2010 and 2020, is a detailed study of the human genome. The second, which he proposes will be completed over the next 20 years, is dedicated to preliminary engineering of genomes. One promising example discussed here is the successful integration into human cells of a gene known to promote protection from radiation in tardigrades, microscopic creatures noted for their extraordinary resilience.

The next stage in Mason’s proposed project involves a series of long-term trials of human and cellular engineering, which he anticipates could be completed between 2041 and 2100, that focus on enhancing our genomic defenses to space radiation. This is the period, he writes, in which “all the genes, cells, and even potentially organs of any organism can become a component of a human cell.”

Between 2101 and 2150, Mason suggests that we begin preparing humans for space. This, he argues, will be a period in which humans will no longer be beholden to naturally transmitted genomes. Genetic modification will be widely used, he predicts, “and it is likely that a significant proportion of people in the United States will be zygotically edited or will be the product of someone who is.”

In phase 5 (2151–2200), Mason predicts that people will be able to move fairly freely between Earth and space bases and that genetic modification will be available to those who want it. In phase 6 (2201–2250), we will make humans tolerant of increasingly more extreme conditions. And in phase 7 (2251–2350), Mason thinks that people will be living in fully developed Martian colonies, intergenerational interstellar travel may be possible, and the DNA of newly discovered life-forms could potentially be sequenced and used to further refine our genomes.

After phase 8 (exoplanetary settlement; 2351–2400), we will enter phase 9 (2401–2500), an era of nearly limitless human possibility. “Humans have the ability to control their underlying genetic code, controlling for how their molecules fundamentally change in response to stimuli and enabling new abilities,” writes Mason. “This will enable an unprecedented ability to build, edit, and transplant cross-kingdom combinations of genomes, which we will need to survive on new worlds.” In Mason’s final phase, “humans will have mastered an ability that truly sets us apart from other species—the ability to direct our own, and other organisms’, evolution.”

Despite sharing a sympathy for the idea of radical genetic modification of humans, I disagree with Mason’s fundamental premise that it is, above all, our duty to protect and extend life in the Universe. There must be a quality to the life we defend, and I question whether radically modified humans in remote space colonies will be truly happy that such a decision has been made on their behalf.

References and Notes:
1. F. E. Garrett-Bakelman et al., Science 364, eaau8650 (2019).

About the author

The reviewer is at the Department of Social Sciences, University of Information Technology and Management in Rzeszów, 35-225 Rzeszów, Poland.