Humans and viruses have had a long and turbulent history together. Like a married couple that can’t stop feuding, we’ve exchanged barbs with these old foes on down the ages. In our present epoch, it’s estimated that as much as 8 percent of human DNA is a relic of ancient viruses – the wreckage of battles long forgotten. But now a group of scientists led by Harvard’s George Church are working to affect a permanent divorce between us and our embattled adversaries, accompanied by a restraining order that would end all contact between the two parties.
If you haven’t heard of Project Recode, you are missing out on one of the most ambitious science experiments of our time. Short of creating human-level artificial intelligence, this might be the single most important scientific undertaking of the modern era. The plan is nothing less than to rewrite the human genetic code with biotechnology and tailor it to our purposes. It would effectively mark the beginning of Humanity 2.0, the creation of a new breed of homo sapiens engineered with superhuman traits — for instance, being impervious to all viruses, and perhaps even cancer as well.
While such lofty aims are well and good, many preliminary goals will have to be realized before attaining this goal. Last week, the scientists behind Project Recode formulated the first of such milestones: modifying specific human tissues to be virus-resistant. How would one even begin such a task? In much the same way you might stop any married couple from feuding — by removing all the furniture from the room.
For viruses to infect humans, they require specific codons, nucleotides that code for amino acids. Humans possess many redundant codons — that is, sequences of genetic code that specify identical amino acids –but these are necessary for viruses to effectively take over a human cell and replicate. By removing redundant codons from our own genome, we could effectively remove all the furniture from the room, halting viruses from replicating. If preliminary experiments are borne out, it would mean the end of the relationship between humans and viruses. What’s more, similar genetic modifications could be used to make humans entirely resistant to cancer as well. Much of the theoretical science behind this is already established, with only one major hurdle remaining – actually trying it out on human tissue.
That’s exactly what the scientists at Project Recode are preparing for, with some generous contributions from the pharmaceutical company Cellectis. But it won’t be easy – they estimate over 400,000 changes to the human genome are required to achieve viral resistance. That’s so many that it doesn’t make sense to use a tool like CRISPR to do the editing. Instead, they’re likely to opt for entirely rewriting the human genome from scratch, synthesizing an artificial genome in the lab. It currently costs about $1 to synthesize 10 DNA letters, according to Stat News. The human genome, with its roughly 3 billion base pairs, would make this a rather expensive proposition. But considering Jeff Bezos is spending $1 billion per year to fund Blue Origin, the price tag for human viral resistance doesn’t seem all that high. What’s a couple billion here or there to remove AIDS and malaria from the human population?
To begin with, the Recode team envisions using such genetically engineered tissues for stem cell therapies or organ transplants, where viral infection of the tissue can lead to disastrous consequences. The sky’s the limit from there, such as potentially modifying germ line cells so the offspring from a couple would be entirely resistant to viruses.
However, given that our ancestors have been co-evolving with viruses for the last several million years, it’s worth pausing to ask if we’re ready to part ways. We’re still only beginning to understand the complicated relationship between humans and viruses. This was borne out in a new study from researchers at the National Institutes of Health and the University of Alabama, Birmingham. The study, published in PLOS Biology, revealed pathogenic infections play an important role in the changing of hair color as we age from its natural pigmentation to gray or white. While this may sound like good news for the Recode Project — after all, who wants their hair to turn gray? — it’s also a warning of sorts, in that we’re mucking about with processes still only partially understood. Viruses may play other unknown roles in activating or dampening the interaction of genes. Some might say we’re moving too fast in eliminating viruses from the human population. Making adjustments to a system we don’t fully understand could lead to unintended consequences.
Perhaps equally disturbing is the lack of public debate. Until now, most of the discussions surrounding Project Recode have occurred within the halls of academia and small scientific circles. While many of the parties involved probably prefer this, since it will expedite their work and avoid bogging down the process in town-hall-style meetings, it nevertheless raises several red flags — not the least of which is why more people aren’t discussing a project that could permanently change the face of the human race. Can you imagine your life had you never had the flu or a fever? Probably not, because it would be so radically different. And it’s worth remembering this isn’t some top secret program being purposefully kept under wraps – the relevant details are all in the public domain.
Instead, it’s likely many people have simply failed to take an interest in the project because they don’t understand its historical relevance, or are too distracted by the flavor-of-the-day political scandal at the White House, to drag themselves away from their social media feed to discuss what should be the limits of biotechnology. Which begs the question: Have Church and his colleagues chosen the wrong target to engineer resistance for? Perhaps a better starting point would be modifying humans to be impervious to celebrity scandals and asinine politicians before attempting something as grandiose as viral resistance.
No one wishes a virus upon their child. But it’s also difficult to take the measure of human culture without the contribution of viruses. Would our libraries be lesser places without the chronicles of Daniel Defoe, Albert Camus, and John Keats, all whom had their writing much influenced by personal battles with viruses? As we continue the long and deliberate march towards engineering human bodies, and societies that are ever more efficient and luxurious, it’s worth reflecting that at least one age-old truth is not likely to change – “the sweet is never as sweet without the sour.”