The news last November that a rogue Chinese scientist had genetically altered the embryos of a pair of Chinese twins shocked the world. But although this use of advanced technology to change the human gene pool was premature, it was a harbinger of how genetic science will alter our healthcare, the way we make babies, the nature of the babies we make, and, ultimately, our sense of who and what we are as a species.
The healthcare applications of the genetics revolution are merely stations along the way to the ultimate destination.
But while the genetics revolution has already begun, we aren't prepared to handle these Promethean technologies responsibly.
By identifying the structure of DNA in the 1950s, Watson, Crick, Wilkins, and Franklin showed that the book of life was written in the DNA double helix. When the human genome project was completed in 2003, we saw how this book of human life could be transcribed. Painstaking research paired with advanced computational algorithms then showed what increasing numbers of genes do and how the genetic book of life can be read.
Now, with the advent of precision gene editing tools like CRISPR, we are seeing that the book of life -- and all biology -- can be re-written. Biology is being recognized as another form of readable, writable, and hackable information technology with we humans as the coders.
The impact of this transformation is being first experienced in our healthcare. Gene therapies including those extracting, re-engineering, then reintroducing a person's own cells enhanced into cancer-fighting supercells are already performing miracles in clinical trials. Thousands of applications have already been submitted to regulators across the globe for trials using gene therapies to address a host of other diseases.
Recently, the first gene editing of cells inside a person's body was deployed to treat the genetically relatively simple metabolic disorder Hunter syndrome, with many more applications to come. These new approaches are only the very first steps in our shift from the current system of generalized medicine based on population averages to precision medicine based on each patient's individual biology to predictive medicine based on AI-generated estimations of a person's future health state.
Jamie Metzl's groundbreaking new book, Hacking Darwin: Genetic Engineering and the Future of Humanity, explores how the genetic revolution is transforming our healthcare, the way we make babies, and the nature of and babies we make, what this means for each of us, and what we must all do now to prepare for what's coming.
This shift in our healthcare will ensure that millions and then billions of people will have their genomes sequenced as the foundation of their treatment. Big data analytics will then be used to compare at scale people's genotypes (what their genes say) to their phenotypes (how those genes are expressed over the course of their lives).
These massive datasets of genetic and life information will then make it possible to go far beyond the simple genetic analysis of today and to understand far more complex human diseases and traits influenced by hundreds or thousands of genes. Our understanding of this complex genetic system within the vaster ecosystem of our bodies and the environment around us will transform healthcare for the better and help us cure terrible diseases that have plagued our ancestors for millennia.
But as revolutionary as this challenge will be for medicine, the healthcare applications of the genetics revolution are merely stations along the way to the ultimate destination – a deep and fundamental transformation of our evolutionary trajectory as a species.
A first inkling of where we are heading can be seen in the direct-to-consumer genetic testing industry. Many people around the world have now sent their cheek swabs to companies like 23andMe for analysis. The information that comes back can tell people a lot about relatively simple genetic traits like carrier status for single gene mutation diseases, eye color, or whether they hate the taste of cilantro, but the information about complex traits like athletic predisposition, intelligence, or personality style today being shared by some of these companies is wildly misleading.
This will not always be the case. As the genetic and health data pools grow, analysis of large numbers of sequenced genomes will make it possible to apply big data analytics to predict some very complex genetic disease risks and the genetic components of traits like height, IQ, temperament, and personality style with increasing accuracy. This process, called "polygenic scoring," is already being offered in beta stage by a few companies and will become an ever bigger part of our lives going forward.
The most profound application of all this will be in our baby-making. Before making a decision about which of the fertilized eggs to implant, women undergoing in vitro fertilization can today elect to have a small number of cells extracted from their pre-implanted embryos and sequenced. With current technology, this can be used to screen for single-gene mutation diseases and other relatively simple disorders. Polygenic scoring, however, will soon make it possible to screen these early stage pre-implanted embryos to assess their risk of complex genetic diseases and even to make predictions about the heritable parts of complex human traits. The most intimate elements of being human will start feeling like high-pressure choices needing to be made by parents.
The limit of our imagination will become the most significant barrier to our recasting biology.
Adult stem cell technologies will then likely make it possible to generate hundreds or thousands of a woman's own eggs from her blood sample or skin graft. This would blow open the doors of reproductive possibility and allow parents to choose embryos with exceptional potential capabilities from a much larger set of options.
The complexity of human biology will place some limits to the extent of possible gene edits that might be made to these embryos, but all of biology, including our own, is extremely flexible. How else could all the diversity of life have emerged from a single cell nearly four billion years ago? The limit of our imagination will become the most significant barrier to our recasting biology.
But while we humans are gaining the powers of the gods, we aren't at all ready to use them.
The same tools that will help cure our worst afflictions, save our children, help us live longer, healthier, more robust lives will also open the door to potential abuses. Prospective parents with the best of intentions or governments with lax regulatory structures or aggressive ideas of how population-wide genetic engineering might be used to enhance national competitiveness or achieve some other goal could propel us into a genetic arms race that could undermine our essential diversity, dangerously divide societies, lead to dangerous, destabilizing, and potentially even deadly conflicts between us, and threaten our very humanity.
But while the advance of genetic technologies is inevitable, how it plays out is anything but. If we don't want the genetic revolution to undermine our species or lead to grave conflicts between genetic haves and have nots or between societies opting in and those opting out, now is the time when we need to make smart decisions based on our individual and collective best values. Although the technology driving the genetic revolution is new, the value systems we will need to optimize the benefits and minimize the harms of this massive transformation are ones we have been developing for thousands of years.
And while some very smart and well-intentioned scientists have been meeting to explore what comes next, it won't be enough for a few of even our wisest prophets to make decisions about the future of our species that will impact everyone. We'll also need smart regulations on both the national and international levels.
Every country will need to have its own regulatory guidelines for human genetic engineering based on both international best practices and the country's unique traditions and values. Because we are all one species, however, we will also ultimately need to develop guidelines that can apply to all of us.
As a first step toward making this possible, we must urgently launch a global, species-wide education effort and inclusive dialogue on the future of human genetic engineering that can eventually inform global norms that will need to underpin international regulations. This process will not be easy, but the alternative of an unregulated genetic arms race would be far worse.
The overlapping genomics and AI revolutions may seem like distant science fiction but are closer than you think. Far sooner than most people recognize, the inherent benefits of these technologies and competition between us will spark rapid adoption. Before that spark ignites, we have a brief moment to come together as a species like we never have before to articulate and translate into action the future we jointly envision. The north star of our best shared values can help us navigate the almost unimaginable opportunities and very real challenges that lie ahead.
Responding to COVID-19 outbreaks at more than 200 mink farms, the Danish government, in November 2020, culled its entire mink population. The Danish armed forces helped farmers slaughter each of their 17 million minks, which are normally farmed for their valuable fur.
The SARS-CoV-2 virus, said officials, spread from human handlers to the small, ferret-like animals, mutated, and then spread back to several hundred humans. Although the mass extermination faced much criticism, Denmark’s prime minister defended the decision last month, stating that the step was “necessary” and that the Danish government had “a responsibility for the health of the entire world.”
Over the past two and half years, COVID-19 infections have been reported in numerous animal species around the world. In addition to the Danish minks, there is other evidence that the virus can mutate as it’s transmitted back and forth between humans and animals, which increases the risk to public health. According to the World Health Organisation (WHO), COVID-19 vaccines for animals may protect the infected species and prevent the transmission of viral mutations. However, the development of such vaccines has been slow. Scientists attribute the deficiency to a lack of data.
“Several animal species have been predicted and found to be susceptible to SARS-CoV-2,” says Suresh V. Kuchipudi, interim director of the Animal Diagnostic Laboratory at the Huck Institutes of Life Sciences. But the risk remains unknown for many animals in several parts of the world, he says. “Therefore, there is an urgent need to monitor the SARS-CoV-2 exposure of high-risk animals in different parts of the world.”
In June, India introduced Ancovax, its first COVID-19 vaccine for animals. The development came a year after the nation reported that the virus had infected eight Asiatic lions, with two of them dying. While 30 COVID-19 vaccines for humans have been approved for general or emergency use across the world, Ancovax is only the third such vaccine for animals. The first, named Carnivac-Cov, was registered by Russia in March last year, followed by another vaccine four months later, developed by Zoetis, a U.S. pharmaceutical company.
Christina Lood, a Zoetis spokesperson, says the company has donated over 26,000 doses of its animal vaccine to over 200 zoos – in addition to 20 conservatories, sanctuaries and other animal organizations located in over a dozen countries, including Canada, Chile and the U.S. The vaccine, she adds, has been administered to more than 300 mammalian species so far.
“At least 75 percent of emerging infectious diseases have an animal origin, including COVID-19,” says Lood. “Now more than ever before, we can all see the important connection between animal health and human health."
The Dangers of COVID-19 Infections among Animals
Cases of the virus in animals have been reported in several countries across the world. As of March this year, 29 kinds of animals have been infected. These include pet animals like dogs, cats, ferrets and hamsters; farmed animals like minks; wild animals like the white-tailed deer, mule deer and black-tailed marmoset; and animals in zoos and sanctuaries, including hyenas, hippopotamuses and manatees. Despite the widespread infection, the U.S. Centres for Diseases Control and Prevention (CDC) has noted that “we don’t yet know all of the animals that can get infected,” adding that more studies and surveillance are needed to understand how the virus is spread between humans and animals.
Leyi Wang, a veterinary virologist at the Veterinary Diagnostic Laboratory, University of Illinois, says that captive and pet animals most often get infected by humans. It goes both ways, he says, citing a recent study in Hong Kong that found the virus spread from pet hamsters to people.
Wang’s bigger concern is the possibility that humans or domestic animals could transmit the virus back to wildlife, creating an uncontrollable reservoir of the disease, especially given the difficulty of vaccinating non-captive wild animals. Such spillbacks have happened previously with diseases such as plague, yellow-fever, and rabies.
It’s challenging and expensive to develop and implement animal vaccines, and demand has been lacking as the broader health risk for animals isn’t well known among the public. People tend to think only about their house pets.
In the past, other human respiratory viruses have proven fatal for endangered great apes like chimpanzees and gorillas. Fearing that COVID-19 could have the same effect, primatologists have been working to protect primates throughout the pandemic. Meanwhile, virus reservoirs have already been created among other animals, Wang says. “Deer of over 20 U.S. states were tested SARS-CoV-2 positive,” says Wang, pointing to a study that confirmed human-to-deer transmission as well as deer-to-deer transmission. It remains unclear how many wildlife species may be susceptible to the disease due to interaction with infected deer, says Wang.
In April, the CDC expressed concerns over new coronavirus variants mutating in wildlife, urging health authorities to monitor the spread of the contagion in animals as threats to humans. The WHO has made similar recommendations.
Challenges to Vaccine Development
Zoetis initiated development activities for its COVID-19 vaccine in February 2020 when the first known infection of a dog occurred in Hong Kong. The pharmaceutical giant completed the initial development work and studies on dogs and cats, and shared their findings at the World One Health Congress in the fall of 2020. A few months later, after a troop of eight gorillas contracted the virus at the San Diego Zoo Safari Park, Zoetis donated its experimental vaccine for emergency use in the great ape population.
Zoetis has uniquely formulated its COVID-19 vaccine for animals. It uses the same antigen as human vaccines, but it includes a different type of carrier protein for inducing a strong immune response. “The unique combination of antigen and carrier ensures safety and efficacy for the species in which a vaccine is used,” says Lood.
But it’s challenging and expensive to develop and implement animal vaccines, and demand has been lacking as the broader health risk for animals isn’t well known among the public. People tend to think only about their house pets. “As it became apparent that risk of severe disease for household pets such as cats and dogs was low, demand for those vaccines decreased before they became commercially available,” says William Karesh, executive vice-president for health and policy at EcoHealth Alliance. He adds that in affected commercial mink farms, the utility of a vaccine could justify the cost in some cases.
Although scientists have made tremendous advances in making vaccines for animals, Kuchipudi thinks that the need for COVID-19 vaccines for animals “must be evaluated based on many factors, including the susceptibility of the particular animal species, health implications, and cost.”.
Not every scientist feels the need for animal vaccines. Joel Baines, a professor of virology at Cornell University’s Baker Institute for Animal Health, says that while domestic cats are the most susceptible to COVID-19, they usually suffer mild infections. Big cats in zoos are vulnerable, but they can be isolated or distanced from humans. He says that mink farms are a relatively small industry and, by ensuring that human handlers are COVID negative, such outbreaks can be curtailed.
Baines also suggests that human vaccines could probably work in animals, as they were tested in animals during early clinical trials and induced immune responses. “However, these vaccines should be used in humans as a priority and it would be unethical to use a vaccine meant for humans to vaccinate an animal if vaccine doses are at all limiting,” he says.
William Karesh, president of the World Animal Health Organization Working Group on Wildlife Diseases, says the best way to protect animals is to reduce their exposure to infected people.
In the absence of enough vaccines, Karesh says that the best way to protect animals is the same as protecting unvaccinated humans - reduce their exposure to infected people by isolating them when necessary. “People working with or spending time with wild animals should follow available guidelines, which includes testing themselves and wearing PPE to avoid accidentally infecting wildlife,” he says.
The Link between Animal and Human Health
Although there is a need for animal vaccines in response to virus outbreaks, the best approach is to try to prevent the outbreaks in the first place, explains K. Srinath Reddy, president of the Public Health Foundation of India. He says that the incidence of zoonotic diseases has increased in the past six decades because human actions like increased deforestation, wildlife trade and animal meat consumption have opened an ecological window for disease transmission between humans and animals. Such actions chip away at the natural barriers between humans and forest-dwelling viruses, while building conveyor belts for the transmission of zoonotic diseases like COVID-19.
Many studies suggest that the source of COVID-19 was infected live animals sold at a wet market in China’s Wuhan. The market sold live dogs, rats, porcupines, badgers, hares, foxes, hedgehogs, marmots and Chinese muntjac (small deer) and, according to a study published in July, the virus was found on the market’s stalls, animal cages, carts and water drains.
This research strongly suggests that COVID-19 is a zoonotic disease, one that jumps from animals to humans due to our close relationship with them in agriculture, as companions and in the natural environment. Half of the infectious diseases that affect people come from animals, but the study of zoonotic diseases has been historically underfunded, even as they can reduce the likelihood and cost of future pandemics.
“We need to invest in vaccines,” says Reddy, “but that cannot be a substitute for an ecologically sensible approach to curtailing zoonotic diseases.”
The Friday Five covers five stories in health research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.