How Should Genetic Engineering Shape Our Future?
Terror. Error. Success. These are the three outcomes that ethicists evaluating a new technology should fear. The possibility that a breakthrough might be used maliciously. The possibility that newly empowered scientists might make a catastrophic mistake. And the possibility that a technology will be so successful that it will change how we live in ways that we can only guess—and that we may not want.
These tools will allow scientists to practice genetic engineering on a scale that is simultaneously far more precise and far more ambitious than ever before.
It was true for the scientists behind the Manhattan Project, who bequeathed a fear of nuclear terror and nuclear error, even as global security is ultimately defined by these weapons of mass destruction. It was true for the developers of the automobile, whose invention has been weaponized by terrorists and kills 3,400 people by accident each day, even as the more than 1 billion cars on the road today have utterly reshaped where we live and how we move. And it is true for the researchers behind the revolution in gene editing and writing.
Put simply, these tools will allow scientists to practice genetic engineering on a scale that is simultaneously far more precise and far more ambitious than ever before. Editing techniques like CRISPR enable exact genetic repairs through a simple cut and paste of DNA, while synthetic biologists aim to redo entire genomes through the writing and substitution of synthetic genes. The technologies are complementary, and they herald an era when the book of life will be not just readable, but rewritable. Food crops, endangered animals, even the human body itself—all will eventually be programmable.
The benefits are easy to imagine: more sustainable crops; cures for terminal genetic disorders; even an end to infertility. Also easy to picture are the ethical pitfalls as the negative images of those same benefits.
Terror is the most straightforward. States have sought to use biology as a weapon at least since invading armies flung the corpses of plague victims into besieged castles. The 1975 biological weapons convention banned—with general success—the research and production of offensive bioweapons, though a handful of lone terrorists and groups like the Oregon-based Rajneeshee cult have still carried out limited bioweapon attacks. Those incidents ultimately caused little death and damage, in part because medical science is mostly capable of defending us from those pathogens that are most easily weaponized. But gene editing and writing offers the chance to engineer germs that could be far more effective than anything nature could develop. Imagine a virus that combines the lethality of Ebola with the transmissibility of the common cold—and in the new world of biology, if you can imagine something, you will eventually be able to create it.
The benefits are easy to imagine: more sustainable crops; cures for terminal genetic disorders; even an end to infertility. Also easy to picture are the ethical pitfalls.
That's one reason why James Clapper, then the U.S. director of national intelligence, added gene editing to the list of threats posed by "weapons of mass destruction and proliferation" in 2016. But these new tools aren't merely dangerous in the wrong hands—they can also be dangerous in the right hands. The list of labs accidents involving lethal bugs is much longer than you'd want to know, at least if you're the sort of person who likes to sleep at night. The U.S. recently lifted a ban on research that works to make existing pathogens, like the H5N1 avian flu virus, more virulent and transmissible, often using new technologies like gene editing. Such work can help medicine better prepare for what nature might throw at us, but it could also make the consequences of a lab error far more catastrophic. There's also the possibility that the use of gene editing and writing in nature—say, by CRISPRing disease-carrying mosquitoes to make them sterile—could backfire in some unforeseen way. Add in the fact that the techniques behind gene editing and writing are becoming simpler and more automated with every year, and eventually millions of people will be capable—through terror or error—of unleashing something awful on the world.
The good news is that both the government and the researchers driving these technologies are increasingly aware of the risks of bioterror and error. One government program, the Functional Genomic and Computational Assessment of Threats (Fun GCAT), provides funding for scientists to scan genetic data looking for the "accidental or intentional creation of a biological threat." Those in the biotech industry know to keep an eye out for suspicious orders—say, a new customer who orders part of the sequence of the Ebola or smallpox virus. "With every invention there is a good use and a bad use," Emily Leproust, the CEO of the commercial DNA synthesis startup Twist Bioscience, said in a recent interview. "What we try hard to do is put in place as many systems as we can to maximize the good stuff, and minimize any negative impact."
But the greatest ethical challenges in gene editing and writing will arise not from malevolence or mistakes, but from success. Through a new technology called in vitro gametogenesis (IVG), scientists are learning how to turn adult human cells like a piece of skin into lab-made sperm and egg cells. That would be a huge breakthrough for the infertile, or for same-sex couples who want to conceive a child biologically related to both partners. It would also open the door to using gene editing to tinker with those lab-made embryos. At first interventions would address any obvious genetic disorders, but those same tools would likely allow the engineering of a child's intelligence, height and other characteristics. We might be morally repelled today by such an ability, as many scientists and ethicists were repelled by in-vitro fertilization (IVF) when it was introduced four decades ago. Yet more than a million babies in the U.S. have been born through IVF in the years since. Ethics can evolve along with technology.
These new technologies offer control over the code of life, but only we as a society can seize control over where these tools will take us.
Fertility is just one human institution that stands to be changed utterly by gene editing and writing, and it's a change we can at least imagine. As the new biology grows more ambitious, it will alter society in ways we can't begin to picture. Harvard's George Church and New York University's Jef Boeke are leading an effort called HGP-Write to create a completely synthetic human genome. While gene editing allows scientists to make small changes to the genome, the gene synthesis that Church and his collaborators are developing allows for total genetic rewrites. "It's a difference between editing a book and writing one," Church said in an interview earlier this year.
Church is already working on synthesizing organs that would be resistant to viruses, while other researchers like Harris Wang at Columbia University are experimenting with bioengineering mammalian cells to produce nutrients like amino acids that we currently need to get from food. The horizon is endless—and so are the ethical concerns of success. What if parents feel pressure to engineer their children just so they don't fall behind their IVG peers? What if only the rich are able to access synthetic biology technologies that could make them stronger, smarter and longer lived? Could inequality become encoded in the genome?
These are questions that are different from the terror and errors fears around biosecurity, because they ask us to think hard about what kind of future we want. To their credit, Church and his collaborators have engaged bioethicists from the start of their work, as have the pioneers behind CRISPR. But the challenges coming from successful gene editing and writing are too large to be outsourced to professional ethicists. These new technologies offer control over the code of life, but only we as a society can seize control over where these tools will take us.
DNA- and RNA-based electronic implants may revolutionize healthcare
Implantable electronic devices can significantly improve patients’ quality of life. A pacemaker can encourage the heart to beat more regularly. A neural implant, usually placed at the back of the skull, can help brain function and encourage higher neural activity. Current research on neural implants finds them helpful to patients with Parkinson’s disease, vision loss, hearing loss, and other nerve damage problems. Several of these implants, such as Elon Musk’s Neuralink, have already been approved by the FDA for human use.
Yet, pacemakers, neural implants, and other such electronic devices are not without problems. They require constant electricity, limited through batteries that need replacements. They also cause scarring. “The problem with doing this with electronics is that scar tissue forms,” explains Kate Adamala, an assistant professor of cell biology at the University of Minnesota Twin Cities. “Anytime you have something hard interacting with something soft [like muscle, skin, or tissue], the soft thing will scar. That's why there are no long-term neural implants right now.” To overcome these challenges, scientists are turning to biocomputing processes that use organic materials like DNA and RNA. Other promised benefits include “diagnostics and possibly therapeutic action, operating as nanorobots in living organisms,” writes Evgeny Katz, a professor of bioelectronics at Clarkson University, in his book DNA- And RNA-Based Computing Systems.
While a computer gives these inputs in binary code or "bits," such as a 0 or 1, biocomputing uses DNA strands as inputs, whether double or single-stranded, and often uses fluorescent RNA as an output.
Adamala’s research focuses on developing such biocomputing systems using DNA, RNA, proteins, and lipids. Using these molecules in the biocomputing systems allows the latter to be biocompatible with the human body, resulting in a natural healing process. In a recent Nature Communications study, Adamala and her team created a new biocomputing platform called TRUMPET (Transcriptional RNA Universal Multi-Purpose GatE PlaTform) which acts like a DNA-powered computer chip. “These biological systems can heal if you design them correctly,” adds Adamala. “So you can imagine a computer that will eventually heal itself.”
The basics of biocomputing
Biocomputing and regular computing have many similarities. Like regular computing, biocomputing works by running information through a series of gates, usually logic gates. A logic gate works as a fork in the road for an electronic circuit. The input will travel one way or another, giving two different outputs. An example logic gate is the AND gate, which has two inputs (A and B) and two different results. If both A and B are 1, the AND gate output will be 1. If only A is 1 and B is 0, the output will be 0 and vice versa. If both A and B are 0, the result will be 0. While a computer gives these inputs in binary code or "bits," such as a 0 or 1, biocomputing uses DNA strands as inputs, whether double or single-stranded, and often uses fluorescent RNA as an output. In this case, the DNA enters the logic gate as a single or double strand.
If the DNA is double-stranded, the system “digests” the DNA or destroys it, which results in non-fluorescence or “0” output. Conversely, if the DNA is single-stranded, it won’t be digested and instead will be copied by several enzymes in the biocomputing system, resulting in fluorescent RNA or a “1” output. And the output for this type of binary system can be expanded beyond fluorescence or not. For example, a “1” output might be the production of the enzyme insulin, while a “0” may be that no insulin is produced. “This kind of synergy between biology and computation is the essence of biocomputing,” says Stephanie Forrest, a professor and the director of the Biodesign Center for Biocomputing, Security and Society at Arizona State University.
Biocomputing circles are made of DNA, RNA, proteins and even bacteria.
Evgeny Katz
The TRUMPET’s promise
Depending on whether the biocomputing system is placed directly inside a cell within the human body, or run in a test-tube, different environmental factors play a role. When an output is produced inside a cell, the cell's natural processes can amplify this output (for example, a specific protein or DNA strand), creating a solid signal. However, these cells can also be very leaky. “You want the cells to do the thing you ask them to do before they finish whatever their businesses, which is to grow, replicate, metabolize,” Adamala explains. “However, often the gate may be triggered without the right inputs, creating a false positive signal. So that's why natural logic gates are often leaky." While biocomputing outside a cell in a test tube can allow for tighter control over the logic gates, the outputs or signals cannot be amplified by a cell and are less potent.
TRUMPET, which is smaller than a cell, taps into both cellular and non-cellular biocomputing benefits. “At its core, it is a nonliving logic gate system,” Adamala states, “It's a DNA-based logic gate system. But because we use enzymes, and the readout is enzymatic [where an enzyme replicates the fluorescent RNA], we end up with signal amplification." This readout means that the output from the TRUMPET system, a fluorescent RNA strand, can be replicated by nearby enzymes in the platform, making the light signal stronger. "So it combines the best of both worlds,” Adamala adds.
These organic-based systems could detect cancer cells or low insulin levels inside a patient’s body.
The TRUMPET biocomputing process is relatively straightforward. “If the DNA [input] shows up as single-stranded, it will not be digested [by the logic gate], and you get this nice fluorescent output as the RNA is made from the single-stranded DNA, and that's a 1,” Adamala explains. "And if the DNA input is double-stranded, it gets digested by the enzymes in the logic gate, and there is no RNA created from the DNA, so there is no fluorescence, and the output is 0." On the story's leading image above, if the tube is "lit" with a purple color, that is a binary 1 signal for computing. If it's "off" it is a 0.
While still in research, TRUMPET and other biocomputing systems promise significant benefits to personalized healthcare and medicine. These organic-based systems could detect cancer cells or low insulin levels inside a patient’s body. The study’s lead author and graduate student Judee Sharon is already beginning to research TRUMPET's ability for earlier cancer diagnoses. Because the inputs for TRUMPET are single or double-stranded DNA, any mutated or cancerous DNA could theoretically be detected from the platform through the biocomputing process. Theoretically, devices like TRUMPET could be used to detect cancer and other diseases earlier.
Adamala sees TRUMPET not only as a detection system but also as a potential cancer drug delivery system. “Ideally, you would like the drug only to turn on when it senses the presence of a cancer cell. And that's how we use the logic gates, which work in response to inputs like cancerous DNA. Then the output can be the production of a small molecule or the release of a small molecule that can then go and kill what needs killing, in this case, a cancer cell. So we would like to develop applications that use this technology to control the logic gate response of a drug’s delivery to a cell.”
Although platforms like TRUMPET are making progress, a lot more work must be done before they can be used commercially. “The process of translating mechanisms and architecture from biology to computing and vice versa is still an art rather than a science,” says Forrest. “It requires deep computer science and biology knowledge,” she adds. “Some people have compared interdisciplinary science to fusion restaurants—not all combinations are successful, but when they are, the results are remarkable.”
In today’s podcast episode, Leaps.org Deputy Editor Lina Zeldovich speaks about the health and ecological benefits of farming crickets for human consumption with Bicky Nguyen, who joins Lina from Vietnam. Bicky and her business partner Nam Dang operate an insect farm named CricketOne. Motivated by the idea of sustainable and healthy protein production, they started their unconventional endeavor a few years ago, despite numerous naysayers who didn’t believe that humans would ever consider munching on bugs.
Yet, making creepy crawlers part of our diet offers many health and planetary advantages. Food production needs to match the rise in global population, estimated to reach 10 billion by 2050. One challenge is that some of our current practices are inefficient, polluting and wasteful. According to nonprofit EarthSave.org, it takes 2,500 gallons of water, 12 pounds of grain, 35 pounds of topsoil and the energy equivalent of one gallon of gasoline to produce one pound of feedlot beef, although exact statistics vary between sources.
Meanwhile, insects are easy to grow, high on protein and low on fat. When roasted with salt, they make crunchy snacks. When chopped up, they transform into delicious pâtes, says Bicky, who invents her own cricket recipes and serves them at industry and public events. Maybe that’s why some research predicts that edible insects market may grow to almost $10 billion by 2030. Tune in for a delectable chat on this alternative and sustainable protein.
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Further reading:
More info on Bicky Nguyen
https://yseali.fulbright.edu.vn/en/faculty/bicky-n...
The environmental footprint of beef production
https://www.earthsave.org/environment.htm
https://www.watercalculator.org/news/articles/beef-king-big-water-footprints/
https://www.frontiersin.org/articles/10.3389/fsufs.2019.00005/full
https://ourworldindata.org/carbon-footprint-food-methane
Insect farming as a source of sustainable protein
https://www.insectgourmet.com/insect-farming-growing-bugs-for-protein/
https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/insect-farming
Cricket flour is taking the world by storm
https://www.cricketflours.com/
https://talk-commerce.com/blog/what-brands-use-cricket-flour-and-why/
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.