CRISPR base editing gives measure of hope to people with muscular dystrophy
When Martin Weber climbs the steps to his apartment on the fifth floor in Munich, an attentive observer might notice that he walks a little unevenly. “That’s because my calf muscles were the first to lose strength,” Weber explains.
About three years ago, the now 19-year-old university student realized that he suddenly had trouble keeping up with his track team at school. At tennis tournaments, he seemed to lose stamina after the first hour. “But it was still within the norm,” he says. “So it took a while before I noticed something was seriously wrong.” A blood test showed highly elevated liver markers. His parents feared he had liver cancer until a week-long hospital visit and scores of tests led to a diagnosis: hereditary limb-girdle muscular dystrophy, an incurable genetic illness that causes muscles to deteriorate.
As you read this text, you will surely use several muscles without being aware of them: Your heart muscle pumps blood through your arteries, your eye muscles let you follow the words in this sentence, and your hand muscles hold the tablet or cell phone. Muscles make up 40 percent of your body weight; we usually have 656 of them. Now imagine they are slowly losing their strength. No training, no protein shake can rebuild their function.
This is the reality for most people in Simone Spuler’s outpatient clinic at the Charité Hospital in Berlin, Germany: Almost all of her 2,500 patients have muscular dystrophy, a progressive illness striking mostly young people. Muscle decline leads to a wheelchair and, eventually, an early death due to a heart attack or the inability to breathe. In Germany alone, 300,000 people live with this illness, the youngest barely a year old. The CDC estimates that its most common form, Duchenne, affects 1 in every 3,500 to 6,000 male births each year in the United States.
The devastating progression of the disease is what motivates Spuler and her team of 25 scientists to find a cure. In 2019, they made a spectacular breakthrough: For the first time, they successfully used mRNA to introduce the CRISPR-Cas9 tool into human muscle stem cells to repair the dystrophy. “It’s really just one tiny molecule that doesn’t work properly,” Spuler explains.
CRISPR-Cas9 is a technology that lets scientists select and alter parts of the genome. It’s still comparatively new but has advanced quickly since its discovery in the early 2010s. “We now have the possibility to repair certain mutations with genetic editing,” Spuler says. “It’s pure magic.”
She projects a warm, motherly air and a professional calm that inspires trust from her patients. She needs these qualities because the 60-year-old neurologist has one of the toughest jobs in the world: All day long, patients with the incurable diagnosis of muscular dystrophy come to her clinic, and she watches them decline over the years. “Apart from physiotherapy, there is nothing we can recommend right now,” she says. That motivated her early in her career, when she met her first patients at the Max Planck Institute for Neurobiology near Munich in the 1990s. “I knew I had 30, 40 years to find something.”
She learned from the luminaries of her profession with postdocs at the University of California San Diego, Harvard and Johns Hopkins, before serving as a clinical fellow at the Mayo Clinic. In 2005, the Charité offered her the opportunity to establish a specialized clinic for myasthenia, or muscular weakness. An important influence on Spuler, she says, has been the French microbiologist Emmanuelle Charpentier, who received the Nobel Prize in 2020 along with Jennifer Doudna for their CRISPR research, and has worked in Berlin since 2015.
When CRISPR was first introduced, it was mainly used to cut through DNA. However, the cut can lead to undesired side effects. For the muscle stem cells, Spuler now uses a base editor to repair the damaged molecule with super fine scissors or tweezers.
“Apart from physiotherapy, there is nothing we can recommend right now,” Spuler says about her patients with limb-girdle muscular dystrophy.
Pablo Castagnola
Last year, she proved that the method works in mice. Injecting repaired cells into the rodents led to new muscle fibers and, in 2021 and 2022, she passed the first safety meetings with the Paul-Ehrlich Institute, which is responsible for approving human gene editing trials in Germany. She raised the nearly four million Euros needed to test the new method in the first clinical trial in humans with limb-girdle muscular dystrophy, beginning with one muscle that can easily be measured, such as the biceps.
This spring, Weber and his parents drove the 400 miles from Munich to Berlin. At Spuler’s lab, her team took a biopsy from muscles in his left arm. The first two steps – extraction and repair in a culture dish – went according to plan; Spuler was able to repair the mutation in Weber’s cells outside his body.
Next year, Weber will be the youngest participant when Spuler starts to test the method in a trial of five people “in vivo,” inside their bodies. This will be the real moment of truth: Will the participants’ muscles accept the corrected cells? Will the cells multiply and take over the function of damaged cells, just like Spuler was able to do in her lab with the rodents?
The effort is costly and complex. “The biggest challenge is to make absolutely sure that we don’t harm the patient,” Spuler says. This means scanning their entire genomes, “so we don’t accidentally damage or knock out an important gene.”
Weber, who asked not to be identified by his real name, is looking forward to the trial and he feels confident that “the risks are comparatively small because the method will only be applied to one muscle. The worst that can happen is that it doesn’t work. But in the best case, the muscle function will improve.”
He was so impressed with the Charité scientists that he decided to study biology at his university. He’s read extensively about CRISPR, so he understands why he has three healthy siblings. “That’s the statistics,” the biologist in training explains. “You get two sets of genes from each parent, and you have to get two faulty mutations to have muscular dystrophy. So we fit the statistics exactly: One of us four kids inherited the mutation.”
It was his mother, a college teacher, and father, a physicist by training, who heard about Spuler’s research. Even though Weber does not live at home anymore, having a chronically ill son is nearly a full-time job for his mother, Annette. The Berlin visit and the trial are financed separately through private sponsors, but the fights with Weber’s health insurance are frustrating and time-consuming. “Physiotherapy is the only thing that helps a bit,” Weber says, “and yet, they fought us on approving it every step of the way.”
Spuler does not want to evoke unrealistic expectations. “Patients who are wheelchair-bound won’t suddenly get up and walk."
Her son continues to exercise as much as possible. Riding his bicycle to the university has become too difficult, so he got an e-scooter. He had to give up competitive tennis because he does not have the stamina for a two-hour match, but he can still play with his dad or his buddies for an hour. His closest friends know about the diagnosis. “They help me, for instance, to lift something heavy because I can’t do that anymore,” Weber says.
The family was elated to find medical support at the Munich Muscle Center by the German Alliance for Muscular Patients and then at Spuler’s clinic in Berlin. “When you hear that this is a progressive illness with no chance of improvement, your world collapses as a parent,” Annette Weber says. “And then all of a sudden, there is this woman who sees scientific progress as an opportunity. Even just to be able to participate in the study is fantastic.”
Spuler does not want to evoke unrealistic expectations. “Patients who are wheelchair-bound won’t suddenly get up and walk,” she says. After all, she will start by applying the gene editor to only one muscle, “but it would be a big step if even a small muscle that is essential to grip something, or to swallow, regains function.”
Weber agrees. “I understand that I won’t regain 100 percent of my muscle function but even a small improvement or at least halting the deterioration is the goal.”
And yet, Spuler and others are ultimately searching for a true solution. In a separate effort, Massachusetts-based biotech company Sarepta announced this month it will seek expedited regulators’ approval to treat Duchenne patients with its investigational gene therapy. Unlike Spuler’s methods, Sarepta focuses specifically on the Duchenne form of muscular dystrophy, and it uses an adeno-assisted virus to deliver the therapy.
Spuler’s vision is to eventually apply gene editing to the entire body of her patients. To speed up the research, she and a colleague founded a private research company, Myopax. If she is able to prove that the body accepts the edited cells, the technique could be used for other monogenetic illnesses as well. “When we speak of genetic editing, many are scared and say, oh no, this is God’s work,” says Spuler. But she sees herself as a mechanic, not a divine being. “We really just exchange a molecule, that’s it.”
If everything goes well, Weber hopes that ten years from now, he will be the one taking biopsies from the next generation of patients and repairing their genes.
Story by Big Think
We live in strange times, when the technology we depend on the most is also that which we fear the most. We celebrate cutting-edge achievements even as we recoil in fear at how they could be used to hurt us. From genetic engineering and AI to nuclear technology and nanobots, the list of awe-inspiring, fast-developing technologies is long.
However, this fear of the machine is not as new as it may seem. Technology has a longstanding alliance with power and the state. The dark side of human history can be told as a series of wars whose victors are often those with the most advanced technology. (There are exceptions, of course.) Science, and its technological offspring, follows the money.
This fear of the machine seems to be misplaced. The machine has no intent: only its maker does. The fear of the machine is, in essence, the fear we have of each other — of what we are capable of doing to one another.
How AI changes things
Sure, you would reply, but AI changes everything. With artificial intelligence, the machine itself will develop some sort of autonomy, however ill-defined. It will have a will of its own. And this will, if it reflects anything that seems human, will not be benevolent. With AI, the claim goes, the machine will somehow know what it must do to get rid of us. It will threaten us as a species.
Well, this fear is also not new. Mary Shelley wrote Frankenstein in 1818 to warn us of what science could do if it served the wrong calling. In the case of her novel, Dr. Frankenstein’s call was to win the battle against death — to reverse the course of nature. Granted, any cure of an illness interferes with the normal workings of nature, yet we are justly proud of having developed cures for our ailments, prolonging life and increasing its quality. Science can achieve nothing more noble. What messes things up is when the pursuit of good is confused with that of power. In this distorted scale, the more powerful the better. The ultimate goal is to be as powerful as gods — masters of time, of life and death.
Should countries create a World Mind Organization that controls the technologies that develop AI?
Back to AI, there is no doubt the technology will help us tremendously. We will have better medical diagnostics, better traffic control, better bridge designs, and better pedagogical animations to teach in the classroom and virtually. But we will also have better winnings in the stock market, better war strategies, and better soldiers and remote ways of killing. This grants real power to those who control the best technologies. It increases the take of the winners of wars — those fought with weapons, and those fought with money.
A story as old as civilization
The question is how to move forward. This is where things get interesting and complicated. We hear over and over again that there is an urgent need for safeguards, for controls and legislation to deal with the AI revolution. Great. But if these machines are essentially functioning in a semi-black box of self-teaching neural nets, how exactly are we going to make safeguards that are sure to remain effective? How are we to ensure that the AI, with its unlimited ability to gather data, will not come up with new ways to bypass our safeguards, the same way that people break into safes?
The second question is that of global control. As I wrote before, overseeing new technology is complex. Should countries create a World Mind Organization that controls the technologies that develop AI? If so, how do we organize this planet-wide governing board? Who should be a part of its governing structure? What mechanisms will ensure that governments and private companies do not secretly break the rules, especially when to do so would put the most advanced weapons in the hands of the rule breakers? They will need those, after all, if other actors break the rules as well.
As before, the countries with the best scientists and engineers will have a great advantage. A new international détente will emerge in the molds of the nuclear détente of the Cold War. Again, we will fear destructive technology falling into the wrong hands. This can happen easily. AI machines will not need to be built at an industrial scale, as nuclear capabilities were, and AI-based terrorism will be a force to reckon with.
So here we are, afraid of our own technology all over again.
What is missing from this picture? It continues to illustrate the same destructive pattern of greed and power that has defined so much of our civilization. The failure it shows is moral, and only we can change it. We define civilization by the accumulation of wealth, and this worldview is killing us. The project of civilization we invented has become self-cannibalizing. As long as we do not see this, and we keep on following the same route we have trodden for the past 10,000 years, it will be very hard to legislate the technology to come and to ensure such legislation is followed. Unless, of course, AI helps us become better humans, perhaps by teaching us how stupid we have been for so long. This sounds far-fetched, given who this AI will be serving. But one can always hope.
Interview with Jamie Metzl: We need a global OS upgrade
In this Q&A, leading technology and healthcare futurist Jamie Metzl discusses a range of topics and trend lines that will unfold over the next several decades: whether a version of Moore's Law applies to genetic technologies, the ethics of genetic engineering, the dangers of gene hacking, the end of sex, and much more.
Metzl is a member of the WHO expert advisory committee on human genome editing and the bestselling author of Hacking Darwin.
The conversation was lightly edited by Leaps.org for style and length.
In Hacking Darwin, you describe how we may modify the human body with CRISPR technologies, initially to obtain unsurpassed sports performance and then to enhance other human characteristics. What would such power over human biology mean for the future of our civilization?
After nearly four billion years of evolution, our one species suddenly has the increasing ability to read, write, and hack the code of life. This will have massive implications across the board, including in human health and reproduction, plant and animal agriculture, energy and advanced materials, and data storage and computing, just to name a few. My book Hacking Darwin: Genetic Engineering and the Future of Humanity primarly explored how we are currently deploying and will increasingly use our capabilities to transform human life in novel ways. My next book, The Great Biohack: Recasting Life in an Age of Revolutionary Technology, coming out in May 2024, will examine the broader implications for all of life on Earth.
We humans will, over time, use these technologies on ourselves to solve problems and eventually to enhance our capabilities. We need to be extremely conservative, cautious, and careful in doing so, but doing so will almost certainly be part of our future as a species.
In electronics, Moore's law is an established theory that computing power doubles every 18 months. Is there any parallel to be drawn with genetic technologies?
The increase in speed and decrease in costs of genome sequencing have progressed far faster than Moore’s law. It took thirteen years and cost about a billion dollars to sequence the first human genome. Today it takes just a few hours and can cost as little as a hundred dollars to do a far better job. In 2012, Jennifer Doudna and Emmanuel Charpentier published the basic science paper outlining the CRISPR-cas9 genome editing tool that would eventually win them the Nobel prize. Only six years later, the first CRISPR babies were born in China. If it feels like technology is moving ever-faster, that’s because it is.
Let's turn to the topic of aging. Do you think that the field of genetics will advance fast enough to eventually increase maximal lifespan for a child born this year? How about for a person who is currently age 50?
The science of aging is definitely real, but that doesn’t mean we will live forever. Aging is a biological process subject to human manipulation. Decades of animal research shows that. This does not mean we will live forever, but it does me we will be able to do more to expand our healthspans, the period of our lives where we are able to live most vigorously.
The first thing we need to do is make sure everyone on earth has access to the resources necessary to live up to their potential. I live in New York City, and I can take a ten minute subway ride to a neighborhood where the average lifespan is over a decade shorter than in mine. This is true within societies and between countries as well. Secondly, we all can live more like people in the Blue Zones, parts of the world where people live longer, on average, than the rest of us. They get regular exercise, eat healthy foods, have strong social connections, etc. Finally, we will all benefit, over time, from more scientific interventions to extend our healthspan. This may include small molecule drugs like metformin, rapamycin, and NAD+ boosters, blood serum infusions, and many other things.
Science fiction has depicted a future where we will never get sick again, stay young longer or become immortal. Assuming that any of this is remotely possible, should we be afraid of such changes, even if they seem positive in some regards, because we can’t understand the full implications at this point?
Not all of these promises will be realized in full, but we will use these technologies to help us live healthier, longer lives. We will never become immortal becasue nothing lasts forever. We will always get sick, even if the balance of diseases we face shifts over time, as it has always done. It is healthy, and absolutely necessary, that we feel both hope and fear about this future. If we only feel hope, we will blind ourselves to the very real potential downsides. If we only feel fear, we will deny ourselves the very meaningful benefits these technologies have the potential to provide.
A fascinating chapter in Hacking Darwin is entitled The End of Sex. And you see that as a good thing?
We humans will always be a sexually reproducing species, it’s just that we’ll reproduce increasingly less through the physical act of sex. We’re already seeing this with IVF. As the benefits of technology assisted reproduction increase relative to reproduction through the act of sex, many people will come to see assisted reproduction as a better way to reduce risk and, over time, possibly increase benefits. We’ll still have sex for all the other wonderful reasons we have it today, just less for reproduction. There will always be a critical place in our world for Italian romantics!
What are dangers of genetic hackers, perhaps especially if everyone’s DNA is eventually transcribed for medical purposes and available on the internet and in the cloud?
The sky is really the limit for how we can use gentic technologies to do things we may want, and the sky is also the limit for potential harms. It’s quite easy to imagine scenarios in which malevolent actors create synthetic pathogens designed to wreak havoc, or where people steal and abuse other people’s genetic information. It wouldn’t even need to be malevolent actors. Even well-intentioned researchers making unintended mistakes could cause real harm, as we may have seen with COVID-19 if, as appears likely to me, the pandemic stems for a research related incident]. That’s why we need strong governance and regulatory systems to optimize benefits and minimize potential harms. I was honored to have served on the World Health Organization Expert Advisory Committee on Human Genome Editing, were we developed a proposed framework for how this might best be achieved.
You foresee the equivalent of a genetic arms race between the world's most powerful countries. In what sense are genetic technologies similar to weapons?
Genetic technologies could be used to create incredibly powerful bioweapons or to build gene drives with the potential to crash entire ecosystems. That’s why thoughtful regulation is in order. Because the benefits of mastering and deploying these technologies are so great, there’s also a real danger of a genetics arms race. This could be extremely dangerous and will need to be prevented.
In your book, you express concern that states lacking Western conceptions of human rights are especially prone to misusing the science of genetics. Does this same concern apply to private companies? How much can we trust them to control and wield these technologies?
This is a conversation about science and technology but it’s really a conversation about values. If we don’t agree on what core values should be promoted, it will be nearly impossible to agree on what actions do and do not make sense. We need norms, laws, and values frameworks that apply to everyone, including governments, corporations, researchers, healthcare providers, DiY bio hobbyists, and everyone else.
We have co-evolved with our technology for a very long time. Many of our deepest beliefs have formed in that context and will continue to do so. But as we take for ourselves the powers we have attributed to our various gods, many of these beliefs will be challenged. We can not and must not jettison our beliefs in the face of technology, and must instead make sure our most cherished values guide the application of our most powerful technologies.
A conversation on international norms is in full swing in the field of AI, prompted by the release of ChatGPT4 earlier this year. Are there ways in which it’s inefficient, shortsighted or otherwise problematic for these discussions on gene technologies, AI and other advances to be occurring in silos? In addition to more specific guidelines, is there something to be gained from developing a universal set of norms and values that applies more broadly to all innovation?
AI is yet another technology where the potential to do great good is tied to the potential to inflict signifcant harm. It makes no sense that we tend to treat each technology on its own rather than looking at the entire category of challenges. For sure, we need to very rapidly ramp up our efforts with regard to AI norm-setting, regulations, and governance at all levels. But just doing that will be kind of like generating a flu vaccine for each individual flu strain. Far better to build a universal flu vaccine addressing common elements of all flu viruses of concern.
That’s why we also need to be far more deliberate in both building a global operating systems based around the mutual responsibilities of our global interdependence and, under that umbrella, a broader system for helping us govern and regulate revolutionary technologies. Such a process might begin with a large international conference, the equivalent of Rio 1992 for climate change, but then quickly work to establish and share best practices, help build parallel institutions in all countries so people and governamts can talk with each other, and do everything possible to maximize benefits and minimize risks at all levels in an ongoing and dynamic way.
At what point might genetic enhancements lead to a reclassfication of modified humans as another species?
We’ll still all be fellow humans for a very, very long time. We already have lots of variation between us. That is the essence of biology. Will some humans, at some point in the future, leave Earth and spend generations elsewhere? I believe so. In those new environments, humans will evolve, over time, differently than those if us who remain on this planet? This may sound like science fiction, but the sci-fi future is coming at us faster than most people realize.
Is the concept of human being changing?
Yes. It always has and always will.
Another big question raised in your book: what limits should we impose on the freedom to manipulate genetics?
Different societies will come to different conclusion on this critical question. I am sympathetic to the argument that people should have lots of say over their own bodies, which why I support abortion rights even though I recognize that an abortion can be a violent procedure. But it would be insane and self-defeating to say that individuals have an unlimited right to manipulate their own or their future children’s heritable genetics. The future of human life is all of our concern and must be regulated, albeit wisely.
In some cases, such as when we have the ability to prevent a deadly genetic disroder, it might be highly ethical to manipulate other human beings. In other circumstances, the genetic engineering of humans might be highly unethical. The key point is to avoid asking this question in a binary manner. We need to weigh the costs and benefits of each type of intervention. We need societal and global infrastrucutres to do that well. We don’t yet have those but we need them badly.
Can you tell us more about your next book?
The Great Biohack: Recasting Lifee in an Age of Revolutionary Technology, will come out in May 2024. It explores what the intersecting AI, genetics, and biotechnology revolutions will mean for the future of life on earth, including our healthcare, agriculture, industry, computing, and everything else. We are at a transitional moment for life on earth, equivalent to the dawn of agriculture, electricity, and industrialization. The key differentiator between better and worse outcomes is what we do today, at this early stage of this new transformation. The book describes what’s happening, what’s at stake, and what we each and all can and, frankly, must do to build the type of future we’d like to inhabit.
You’ve been a leader of international efforts calling for a full investigation into COVID-19 origins and are the founder of the global movement OneShared.World. What problem are you trying to solve through OneShared.World?
The biggest challenge we face today is the mismatch between the nature of our biggest problems, global and common, and the absence of a sufficient framework for addressing that entire category of challenges. The totally avoidable COVID-19 pandemic is one example of the extremet costs of the status quo. OneShared.World is our effort to fight for an upgrade in our world’s global operating system, based around the mutual responsibilities of interdependence. We’ve had global OS upgrades before after the Thirty Years War and after World War II, but wouldn’t it be better to make the necessary changes now to prevent a crisis of that level stemming from a nuclear war, ecosystem collapse, or deadlier synthetic biology pandemic rather than waiting until after? Revolutionary science is a global issue that must be wisely managed at every level if it is to be wisely managed at all.
How do we ensure that revolutionary technologies benefit humanity instead of undermining it?
That is the essential question. It’s why I’ve written Hacking Darwin, am writing The Great Biohack, and doing the rest of my work. If we want scietific revolutions to help, rather than hurt, us, we must all play a role building that future. This isn’t just a conversation about science, it’s about how we can draw on our most cherished values to guide the optimal development of science and technology for the common good. That must be everyone’s business.
Portions of this interview were first published in Grassia (Italy) and Zen Portugal.
Jamie Metzl is one of the world’s leading technology and healthcare futurists and author of the bestselling book, Hacking Darwin: Genetic Engineering and the Future of Humanity, which has been translated into 15 languages. In 2019, he was appointed to the World Health Organization expert advisory committee on human genome editing. Jamie is a faculty member of Singularity University and NextMed Health, a Senior Fellow of the Atlantic Council, and Founder and Chair of the global social movement, OneShared.World.
Called “the original COVID-19 whistleblower,” his pioneering role advocating for a full investigation into the origins of the COVID-19 pandemic has been featured in 60 Minutes, the New York Times, and most major media across the globe, and he was the lead witness in the first congressional hearings on this topic. Jamie previously served in the U.S. National Security Council, State Department, and Senate Foreign Relations Committee and with the United Nations in Cambodia. Jamie appears regularly on national and international media and his syndicated columns and other writing in science, technology, and global affairs are featured in publications around the world.
Jamie sits on advisory boards for multiple biotechnology and other companies and is Special Strategist to the WisdomTree BioRevolution Exchange Traded Fund. In addition to Hacking Darwin, he is author of a history of the Cambodian genocide, the historical novel The Depths of the Sea, and the genetics sci-fi thrillers Genesis Code and Eternal Sonata. His next book, The Great Biohack: Recasting Life in an age of Revolutionary Technology, will be published by Hachette in May 2024. Jamie holds a Ph.D. from Oxford, a law degree from Harvard, and an undergraduate degree from Brown and is an avid ironman triathlete and ultramarathon runner.