The First Cloned Monkeys Provoked More Shrugs Than Shocks
A few months ago, it was announced that not one, but two healthy long-tailed macaque monkeys were cloned—a first for primates of any kind. The cells were sourced from aborted monkey fetuses and the DNA transferred into eggs whose nuclei had been removed, the same method that was used in 1996 to clone "Dolly the Sheep." Two live births, females named Zhong Zhong and Hua Hua, resulted from 60 surrogate mothers. Inefficient, it's true. But over time, the methods are likely to be improved.
The scientist who supervised the project predicts that cloning, along with gene editing, will result in "ideal primate models" for studying disease mechanisms and drug screening.
Dr. Gerald Schatten, a famous would-be monkey cloner, authored a controversial paper in 2003 describing the formidable challenges to cloning monkeys and humans, speculating that the feat might never be accomplished. Now, some 15 years later, that prediction, insofar as it relates to monkeys, has blown away.
Zhong Zhong and Hua Hua were created at the Chinese Academy of Science's Institute of Neuroscience in Shanghai. The Institute founded in 1999 boasts 32 laboratories, expanding to 50 labs in 2020. It maintains two non-human primate research facilities.
The founder and director, Dr. Mu-ming Poo, supervised the project. Poo is an extremely accomplished senior researcher at the pinnacle of his field, a distinguished professor emeritus in Biology at UC Berkeley. In 2016, he was awarded the prestigious $500,000 Gruber Neuroscience Prize. At that time, Poo's experiments were described by a colleague as being "innovative and very often ingenious."
Poo maintains the reputation of studying some of the most important questions in cellular neuroscience.
But is society ready to accept cloned primates for medical research without the attendant hysteria about fears of cloned humans?
By Western standards, use of non-human primates in research focuses on the welfare of the animal subjects. As PETA reminds us, there is a dreadful and sad history of mistreatment. Dr. Poo assures us that his cloned monkeys are treated ethically and that the Institute is compliant with the highest regulatory standards, as promulgated by the U.S. National Institutes of Health.
He presents the noblest justifications for the research. He predicts that cloning, along with gene editing, will result in "ideal primate models" for studying disease mechanisms and drug screening. He declares that this will eventually help to solve Parkinson's, Huntington's and Alzheimer's disease.
But is society ready to accept cloned primates for medical research without the attendant hysteria about fears of cloned humans? It appears so.
While much of the news coverage expressed this predictable worry, my overall impression is that the societal response was muted. Where was the expected outrage? Then again, we've come a long way since Dolly the Sheep in terms of both the science and the cultural acceptance of cloning. Perhaps my unique vantage point can provide perspective on how much attitudes have evolved.
Perhaps my unique vantage point can provide perspective on how much attitudes have evolved.
I sometimes joke that I am the world's only human cloning lawyer—a great gig but there are still no clients.
I first crashed into the cloning scene in 2002 when I sued the so-called human cloning company "Clonaid" and asked in court to have a temporary guardian appointed for the alleged first human clone "Baby Eve." The claim needed to be tested, and mine was the first case ever aiming to protect the rights of a human clone. My legal basis was child welfare law, protecting minors from abuse, negligence, and exploitation.
The case had me on back-to-back global television broadcasts around the world; there was live news and "breathless" coverage at the courthouse emblazoned in headlines in every language on the planet. Cloning was, after all, perceived as a species-altering event: asexual reproduction. The controversy dominated world headlines for month until Clonaid's claim was busted as the "fakest" of fake news.
Fresh off the cloning case, the scientific community reached out to me, seeing me as the defender of legitimate science, an opponent of cloning human babies but a proponent of using cloning techniques to accelerate ethical regenerative medicine and embryonic stem cell research in general.
The years 2003 to 2006 were the era of the "stem cell wars" and a dominant issue was human cloning. Social conservative lawmakers around the world were seeking bans or criminalization not only of cloning babies but also the cloning of cells to match the donor's genetics. Scientists were being threatened with fines and imprisonment. Human cloning was being challenged in the United Nations with the United States backing a global treaty to ban and morally condemn all cloning -- including the technique that was crucial for research.
Scientists and patients were touting the cloning technique as a major biomedical breakthrough because cells could be created as direct genetic matches from a specific donor.
At the same time, scientists and patients were touting the cloning technique as a major biomedical breakthrough because cells could be created as direct genetic matches from a specific donor.
So my organization organized a conference at UN headquarters to defend research cloning and all the big names in stem cell research were there. We organized petitions to the UN and faxed 35,000 signatures to the country mission. These ongoing public policy battles were exacerbated in part because of the growing fear that cloning babies was just around the corner.
Then in 2005, the first cloned dog stunned the world, an Afghan hound named Snuppy. I met him when I visited the laboratories of Professor Woo Suk Hwang in Korea. His minders let me hold his leash -- TIME magazine's scientific breakthrough of the year. He didn't lick me or even wag his tail; I figured he must not like lawyers.
Tragically, soon thereafter, I witnessed firsthand Dr. Hwang's fall from grace when his human stem cell cloning breakthroughs proved false. The massive scientific misconduct rocked the nation of Korea, stem cell science in general, and provoked terrible news coverage.
Nevertheless, by 2007, the proposed bans lost steam, overridden by the advent of a Japanese researcher's Nobel Prize winning formula for reprogramming human cells to create genetically matched cell lines, not requiring the destruction of human embryos.
After years of panic, none of the recent cloning headlines has caused much of a stir.
Five years later, when two American scientists accomplished therapeutic human cloned stem cell lines, their news was accepted without hysteria. Perhaps enough time had passed since Hwang and the drama was drained.
In the just past 30 days we have seen more cloning headlines. Another cultural icon, Barbara Streisand, revealed she owns two cloned Coton de Tulear puppies. The other weekend, the television news show "60 Minutes" devoted close to an hour on the cloned ponies used at the top level of professional polo. And in India, scientists just cloned the first Assamese buffalo.
And you know what? After years of panic, none of this has caused much of a stir. It's as if the future described by Alvin Toffler in "Future Shock" has arrived and we are just living with it. A couple of cloned monkeys barely move the needle.
Perhaps it is the advent of the Internet and the overall dilution of wonder and outrage. Or maybe the muted response is rooted in popular culture. From Orphan Black to the plotlines of dozens of shows and books, cloning is just old news. The hand-wringing discussions about "human dignity" and "slippery slopes" have taken a backseat to the AI apocalypse and Martian missions.
We humans are enduring plagues of dementia and Alzheimer's, and we will need more monkeys. I will take mine cloned, if it will speed progress.
Personally, I still believe that cloned children should not be an option. Child welfare laws might be the best deterrent.
The same does not hold for cloning monkey research subjects. Squeamishness aside, I think Zhong Zhong and Hua Hua will soon be joined by a legion of cloned macaques and probably marmosets.
We humans are enduring plagues of dementia and Alzheimer's, and we will need more monkeys. I will take mine cloned, if it will speed the mending of these consciousness-destroying afflictions.
Scientific revolutions once took centuries, then decades, and now seem to bombard us daily. The convergence of technologies has accelerated the future. To Zhong Zhong and Hua Hua, my best wishes with the hope that their sacrifices will contribute to the health of all primates -- not just humans.
Later this year, Verve Therapeutics of Cambridge, Ma., will initiate Phase 1 clinical trials to test VERVE-101, a new medication that, if successful, will employ gene editing to significantly reduce low-density lipoprotein cholesterol, or LDL.
LDL is sometimes referred to as the “bad” cholesterol because it collects in the walls of blood vessels, and high levels can increase chances of a heart attack, cardiovascular disease or stroke. There are approximately 600,000 heart attacks per year due to blood cholesterol damage in the United States, and heart disease is the number one cause of death in the world. According to the CDC, a 10 percent decrease in total blood cholesterol levels can reduce the incidence of heart disease by as much as 30 percent.
Verve’s Founder and CEO, Sekar Kathiresan, spent two decades studying the genetic basis for heart attacks while serving as a professor of medicine at Harvard Medical School. His research led to two critical insights.
“One is that there are some people that are naturally resistant to heart attack and have lifelong, low levels of LDL,” the cardiologist says. “Second, there are some genes that can be switched off that lead to very low LDL cholesterol, and individuals with those genes switched off are resistant to heart attacks.”
Kathiresan and his team formed a hypothesis in 2016 that if they could develop a medicine that mimics the natural protection that some people enjoy, then they might identify a powerful new way to treat and ultimately prevent heart attacks. They launched Verve in 2018 with the goal of creating a one-time therapy that would permanently lower LDL and eliminate heart attacks caused by high LDL.
"Imagine a future where somebody gets a one-time treatment at the time of their heart attack or before as a preventive measure," says Kathiresan.
The medication is targeted specifically for patients who have a genetic form of high cholesterol known as heterozygous familial hypercholesterolemia, or FH, caused by expression of a gene called PCSK9. Verve also plans to develop a program to silence a gene called ANGPTL3 for patients with FH and possibly those with or at risk of atherosclerotic cardiovascular disease.
FH causes cholesterol to be high from birth, reaching levels of 200 to 300 milligrams per deciliter. Suggested normal levels are around 100 to 129 mg/dl, and anything above 130 mg/dl is considered high. Patients with cardiovascular disease usually are asked to aim for under 70 mg/dl, but many still have unacceptably high LDL despite taking oral medications such as statins. They are more likely to have heart attacks in their 30s, 40s and 50s, and require lifelong LDL control.
The goal for drug treatments for high LDL, Kathiresan says, is to reduce LDL as low as possible for as long as possible. Physicians and researchers also know that a sizeable portion of these patients eventually start to lose their commitment to taking their statins and other LDL-controlling medications regularly.
“If you ask 100 patients one year after their heart attack what fraction are still taking their cholesterol-lowering medications, it’s less than half,” says Kathiresan. “So imagine a future where somebody gets a one-time treatment at the time of their heart attack or before as a preventive measure. It’s right in front of us, and it’s something that Verve is looking to do.”
In late 2020, Verve completed primate testing with monkeys that had genetically high cholesterol, using a one-time intravenous injection of VERVE-101. It reduced the monkeys’ LDL by 60 percent and, 18 months later, remains at that level. Kathiresan expects the LDL to stay low for the rest of their lives.
Verve’s gene editing medication is packaged in a lipid nanoparticle to serve as the delivery mechanism into the liver when infused intravenously. The drug is absorbed and makes its way into the nucleus of the liver cells.
Verve’s program targeting PCSK9 uses precise, single base, pair base editing, Kathiresan says, meaning it doesn't cut DNA like CRISPR gene editing systems do. Instead, it changes one base, or letter, in the genome to a different one without affecting the letters around it. Comparing it to a pencil and eraser, he explains that the medication erases out a letter A and makes it a letter G in the A, C, G and T code in DNA.
“We need to continue to advance our approach and tools to make sure that we have the absolute maximum ability to detect off-target effects,” says Euan Ashley, professor of medicine and genetics at Stanford University.
By making that simple change from A to G, the medication switches off the PCSK9 gene, automatically lowering LDL cholesterol.
“Once the DNA change is made, all the cells in the liver will have that single A to G change made,” Kathiresan says. “Then the liver cells divide and give rise to future liver cells, but every time the cell divides that change, the new G is carried forward.”
Additionally, Verve is pursuing its second gene editing program to eliminate ANGPTL3, a gene that raises both LDL and blood triglycerides. In 2010, Kathiresan's research team learned that people who had that gene completely switched off had LDL and triglyceride levels of about 20 and were very healthy with no heart attacks. The goal of Verve’s medication will be to switch off that gene, too, as an option for additional LDL or triglyceride lowering.
“Success with our first drug, VERVE-101, will give us more confidence to move forward with our second drug,” Kathiresan says. “And it opens up this general idea of making [genomic] spelling changes in the liver to treat other diseases.”
The approach is less ethically concerning than other gene editing technologies because it applies somatic editing that affects only the individual patient, whereas germline editing in the patient’s sperm or egg, or in an embryo, gets passed on to children. Additionally, gene editing therapies receive the same comprehensive amount of testing for side effects as any other medicine.
“We need to continue to advance our approach and tools to make sure that we have the absolute maximum ability to detect off-target effects,” says Euan Ashley, professor of medicine and genetics at Stanford University and founding director of its Center for Inherited Cardiovascular Disease. Ashley and his colleagues at Stanford’s Clinical Genomics Program and beyond are increasingly excited about the promise of gene editing.
“We can offer precision diagnostics, so increasingly we’re able to define the disease at a much deeper level using molecular tools and sequencing,” he continues. “We also have this immense power of reading the genome, but we’re really on the verge of taking advantage of the power that we now have to potentially correct some of the variants that we find on a genome that contribute to disease.”
He adds that while the gene editing medicines in development to correct genomes are ahead of the delivery mechanisms needed to get them into the body, particularly the heart and brain, he’s optimistic that those aren’t too far behind.
“It will probably take a few more years before those next generation tools start to get into clinical trials,” says Ashley, whose book, The Genome Odyssey, was published last year. “The medications might be the sexier part of the research, but if you can’t get it into the right place at the right time in the right dose and not get it to the places you don’t want it to go, then that tool is not of much use.”
Medical experts consider knocking out the PCSK9 gene in patients with the fairly common genetic disorder of familial hypercholesterolemia – roughly one in 250 people – a potentially safe approach to gene editing and an effective means of significantly lowering their LDL cholesterol.
Nurse Erin McGlennon has an Implantable Cardioverter Defibrillator and takes medications, but she is also hopeful that a gene editing medication will be developed in the near future.
Erin McGlennon
Mary McGowan, MD, chief medical officer for The Family Heart Foundation in Pasadena, CA, sees the tremendous potential for VERVE-101 and believes patients should be encouraged by the fact that this kind of research is occurring and how much Verve has accomplished in a relatively short time. However, she offers one caveat, since even a 60 percent reduction in LDL won’t completely eliminate the need to reduce the remaining amount of LDL.
“This technology is very exciting,” she said, “but we want to stress to our patients with familial hypercholesterolemia that we know from our published research that most people require several therapies to get their LDL down., whether that be in primary prevention less than 100 mg/dl or secondary prevention less than 70 mg/dl, So Verve’s medication would be an add-on therapy for most patients.”
Dr. Kathiresan concurs: “We expect our medicine to lower LDL cholesterol by about 60 percent and that our patients will be on background oral medications, including statins that lower LDL cholesterol.”
Several leading research centers are investigating gene editing treatments for other types of cardiovascular diseases. Elizabeth McNally, Elizabeth Ward Professor and Director at the Center for Genetic Medicine at Northwestern University’s Feinberg School of Medicine, pursues advanced genetic correction in neuromuscular diseases such as Duchenne muscular dystrophy and spinal muscular atrophy. A cardiologist, she and her colleagues know these diseases frequently have cardiac complications.
“Even though the field is driven by neuromuscular specialists, it’s the first therapies in patients with neuromuscular diseases that are also expected to make genetic corrections in the heart,” she says. “It’s almost like an afterthought that we’re potentially fixing the heart, too.”
Another limitation McGowan sees is that too many healthcare providers are not yet familiar with how to test patients to determine whether or not they carry genetic mutations that need to be corrected. “We need to get more genetic testing done,” she says. “For example, that’s the case with hypertrophic cardiomyopathy, where a lot of the people who probably carry that diagnosis and have never been genetically identified at a time when genetic testing has never been easier.”
One patient who has been diagnosed with hypertrophic cardiomyopathy also happens to be a nurse working in research at Genentech Pharmaceutical, now a member of the Roche Group, in South San Francisco. To treat the disease, Erin McGlennon, RN, has an Implantable Cardioverter Defibrillator and takes medications, but she is also hopeful that a gene editing medication will be developed in the near future.
“With my condition, the septum muscles are just growing thicker, so I’m on medicine to keep my heart from having dangerous rhythms,” says McGlennon of the disease that carries a low risk of sudden cardiac death. “So, the possibility of having a treatment option that can significantly improve my day-to-day functioning would be a major breakthrough.”
McGlennon has some control over cardiovascular destiny through at least one currently available technology: in vitro fertilization. She’s going through it to ensure that her children won't express the gene for hypertrophic cardiomyopathy.
More than 20 percent of American adults suffer from chronic pain. And as many as one in four of those prescribed opioids to manage that pain go on to misuse – or abuse – them, often with devastating consequences. Patients afflicted by both chronic pain and opioid addiction are especially difficult to treat, according to Eric Garland, PhD, Director of the University of Utah’s Center on Mindfulness and Integrative Health Intervention Development, because opioid overuse increases pain sensitivity, and pain promotes relapse among those being treated for addiction.
A new study, however, shows that a mindfulness-based therapy can successfully tackle both problems at once, pointing to a tool that could potentially help in fighting the opioid crisis. “This is the first large-scale clinical trial to show that any psychological intervention can reduce opioid misuse and chronic pain for the long term,” says Garland, lead author of the study, published February 28th in JAMA Internal Medicine.
Garland’s study focused on 250 adults who had received opioid therapy for chronic pain for 90 days or longer, randomly assigning them to eight weeks of either a standard psychotherapy support group or Mindfulness-Oriented Recovery Enhancement (MORE) therapy, which combines mindfulness training, cognitive-behavioral therapy (CBT) and positive psychology. Nine months after getting these treatments in primary care settings, 45 percent of patients in the MORE group were no longer misusing opioids, compared to 24 percent of those in group therapy. In fact, about a third of the patients in the MORE group were able to cut their opioid dose in half or reduce it even further.
Patients treated with MORE also experienced more significant pain relief than those in support groups, according to Garland. Conventional approaches to treating opioid addiction include 12-step programs and medically-assisted treatment using drugs like methadone and Suboxone, sometimes coupled with support groups. But patients with Opioid Use Disorder (OUD) – the official diagnosis for opioid addiction – have high relapse rates following treatment, especially if they have chronic pain.
While medically-assisted treatments help to control drug cravings, they do nothing to control chronic pain, which is where psychological therapies like MORE come in.
“For patients suffering from moderate pain and OUD, the relapse rate is three times higher than in patients without chronic pain; for those with severe chronic pain, the relapse rate is five times higher,” says Amy Wachholtz, PhD, Director of Clinical Health Psychology and associate professor at University of Colorado in Denver. “So if we don’t treat the chronic pain along with the OUD addiction simultaneously, we are setting patients up for failure.”
Unfortunately, notes Garland, the standard of care for patients with chronic pain who are misusing their prescribed painkillers is “woefully inadequate.” Many patients don’t meet the criteria for OUD, he says, but instead fall into a gray zone somewhere between legitimate opioid use and full-blown addiction. And while medically-assisted treatments help to control drug cravings, they do nothing to control chronic pain, which is where psychological therapies like MORE come in. But behavioral therapies are often not available in primary care settings, and even when clinicians do refer patients to behavioral health providers, they often prescribe CBT. A large scale study last year showed that CBT – without the added components of mindfulness training and positive psychology – reduced pain but not opioid misuse.
Psychotherapist Eric Garland teaches mindfulness.
University of Utah
Reward Circuitry Rewired
Opioids are highly physiologically addictive. Repeated and high-dose drug use causes the brain to become hypersensitive to stress, pain, and drug-related cues, such as the sight of one’s pill bottle, says Garland, while at the same time becoming increasingly insensitive to natural pleasures. “As an individual becomes more and more dependent on the opioids just to feel okay, they feel less able to extract a healthy sense of joy, pleasure and meaning out of everyday life,” he explains. “This drives them to take higher and higher doses of the opioid to maintain a dwindling sense of well-being.”
The changes are not just psychological: Chronic opioid use actually causes changes in the brain’s reward circuitry. “You can see on brain imaging,” says Garland. “The brain’s reward circuitry becomes more responsive when a person is viewing opioid related images than when they are viewing images of smiling babies, lovers holding hands, or sunsets over the beach.” MORE, he says, teaches “savoring” – a tenet of positive psychology – as a means of restructuring the reward processes in the brain so the patient becomes sensitive to pleasure from natural, healthy rewards, decreasing cravings for drug-related rewards.
Mindfulness and Addiction
Mindfulness, a form of meditation that teaches people to observe their feelings and sensations without judgement, has been increasingly applied to the treatment of addiction. By observing their pain and cravings objectively, for example, patients gain increased awareness of their responses to pain and their habits of opioid use. “They learn how to be with discomfort, whether emotional or physical, in a more compassionate way,” says Sarah Bowen, PhD, associate professor of psychology at Pacific University in Oregon. “And if your mind gives you a message like ‘Oh, I can’t handle that,’ to recognize that that’s a thought that might not be true.”
Bowen’s research is focused on Mindfulness-Based Relapse Prevention, which addresses the cravings associated with addiction. She has patients practice what she calls “urge surfing”: riding out a craving or urge rather than relying on a substance for immediate relief. “Craving will happen, so rather than fighting it, we look at understanding it better,” she says.
MORE differs from other forms of mindfulness-based therapy in that it integrates reappraisal and savoring training. Reappraisal is a technique often used in CBT in which patients learn to change negative thought patterns in order to reduce their emotional impact, while savoring helps to restructure the reward processes in the brain.
Mindfulness training not only helps patients to understand and gain control over their behavior in response to cravings and triggers like pain, says Garland, but also provides a means of pain relief. “We use mindfulness to zoom into pain and break it down into its subcomponents – feelings of heat or tightness or tingling – which reduces the impact that negative emotions have on pain processing in the brain.”
Eric Garland examines brain waves.
University of Utah
Powerful interventions
As the dangers of opioid addiction have become increasingly evident, some scientists are developing less addictive, non-opioid painkillers, but more trials are needed. Meanwhile, behavioral approaches to chronic pain relief have continued to gain traction, and researchers like Garland are probing the possibilities of integrative treatments to treat the addiction itself. Given that the number of people suffering from chronic pain and OUD have reached new heights during the COVID-19 pandemic, says Wachholtz, new treatment alternatives for patients caught in the relentless cycle of chronic pain and opioid misuse are sorely needed. “We’re trying to refine the techniques,” she says, “but we’re starting to realize just how powerful some of these mind-body interventions can be.”