Animal Models v2 wotext-1

Written by Michelle Frank, Alexandra Schnell, Mashaal Sohail, and Amy Gilson

Part Two (Listen to Part One here)

Amy– Episode intro Hello, and welcome to Sit’N Listen: a production of Science in the News. We’re a graduate-student run organization at Harvard University that catalyzes discussion between scientists and other experts and enthusiasts. I’m Amy Gilson, a producer of Sit’N Listen and also a graduate student. I’m studying how proteins evolve using computer simulations, data analysis, and experiments in bacteria. Today, we’re continuing with our part two of our episode on animal experimentation. If you haven’t listened to Part One, you can go back and listen to Part One it on iTunes or our SoundCloud page if you just look up Sit’N Listen, but Part Two will still make sense if you just keep listening now. But before we get started, let’s just go around and introduce ourselves again.

Mashaal My name is Mashaal Sohail, and I’m a PhD candidate in systems biology at Harvard. My research is focused on studying natural selection in modern humans.

Michelle My name is Michelle Frank, and I’m a PhD candidate in neuroscience here at Harvard. My research is focused on the auditory system. Over the course of my scientific career so far, I’ve worked with fruit flies, worms, fish, mice, and humans.

Alex And I’m Alexandra Schnell. I just started my graduate work in immunology, and I’ll be working on autoimmune diseases using mouse models.

Michelle– What we’ve learned from Drosophila  As a neuroscientist who works with fruit flies, one of the most common questions I’m asked is, “wait, fruit flies have brains?” Luckily for me, they do have brains. Confusion about what simple model organisms like fruit flies and worms can teach us about pressing biomedical problems is also shared by more than a few politicians: Sarah Palin quote

That quote, of course, is from Sarah Palin. And while her umbridge at fruit fly research might seem a bit extreme, skepticism about the use of simple model systems in biomedical research is understandable. At first glance, human beings and insects seem to have very little in common with each other. For one thing, humans don’t have wings. More significantly, fruit flies lack a spinal cord; they have multifaceted, compound eyes. They don’t even have blood, although they do have a different kind of circulating fluid. So what on earth can fruit flies teach us about human health?

As it turns out, rather a lot. Roughly half of the human genome is shared with our insect cousin, and, as that number might suggest, many core aspects of biology are indeed shared between humans and fruit flies. Much of what we know about genetics was originally discovered in Drosophila, and studies in the fly have also had a major impact on our understanding of how a fertilized egg develops into an adult animal. Scientists today are also using Drosophila to model many human diseases, including cancer, autism, and Alzheimer’s disease.

Amy That’s really weird.

Michelle Yeah, but these studies can have real consequences for human health. Think about your circadian clock, your body’s internal timekeeping mechanism. [Sound effect: Clock ticking] Your circadian clock might prevent you from sleeping in on weekends if you’re used to waking up early, and if you’ve ever traveled to a distant time zone, you can thank your circadian clock for the delightful effects of jetlag. Disruptions in circadian rhythms have also been linked to an increased risk for cancer and a poorer prognosis for patients with the disease. There’s hope, then, that a better understanding of the body’s circadian rhythms can lead to new for anticancer therapies, as well as treatments for insomnia and jet lag.

And here’s where fruit flies come in. Like humans, fruit flies have a circadian clock—as do plants, fungi, and even many bacteria. Like humans, fruit flies sleep, and their sleep patterns are determined by their circadian rhythms. Like humans, fruit flies get jet lag if you suddenly start turning the lights on and off a few hours earlier or later than they’re used to. And, like humans, fruit flies keep track of the time of day with a molecular clock that shares many of its fundamental elements with the molecular clock in humans.

By the mid-twentieth century, scientists could list numerous ways that organisms rely on biological clocks: some animals are nocturnal and others are diurnal, and they maintain these rhythms even in laboratories where all environmental cues have been wiped away. As late as the 1970s, though, biologists had very little idea how any of this worked. As Jonathon Weiner describes in his book Time, Love, Memory, the problem seemed so intractable in the mid 1900s that one botanist insisted the field would need “another Newton” to find the solution.

In 1971, two years after that challenge was issued, Ronald Konopka and Seymour Benzer identified the first component of the molecular clock in Drosophila, a gene they called period. In time, researchers were able to use this knowledge about the period gene in the fly to identify period genes in humans and mice. Gradually, work in several species has helped to identify even more components of this molecular timepiece. Nearly all of the genes known to be key regulators of the circadian clock were first identified in flies.

When I say that the period gene were found in both flies and humans, I don’t mean that you can find identical chunks of period DNA coiled into the genomes of both Homo sapiens and Drosophila melanogaster. What I mean is that both fruit flies and humans have a segment of DNA that looks quite similar, and this segment of DNA serves as a blueprint for a protein that does similar things in both flies and humans. Scientists say that these genes, these bits of similar genetic material, are “conserved” between humans and flies. As organisms evolve, their genomes diverge, their differences expand, and they develop wildly different traits. Still, some traits are sufficiently important to the survival of the organism that they deviate very little over time, because even small variations in these core traits generally lead to major defects or death. In biology, we say that these core traits are conserved between species and across evolutionary time.

That isn’t to say there isn’t wiggle room: mammals have three period genes, for instance, while flies have only one. Still, we know that there are three period genes because identifying the single gene in Drosophila told researchers what to look for in humans. Konopka and Benzer were able to identify the period gene in the first place because working with flies allowed them to look at hundreds of mutant animals until they identified some with time-keeping defects. Performing a similar experiment with mice or humans would have been prohibitively expensive, time-consuming, and inhumane.

Alex– Let’s talk diabetes with mice So maybe mice weren’t the best system for identifying circadian genes and aren’t ideal for experiments that require scientists to look at hundreds and hundreds of mutant animals. But there are also many things we can study in mice that just can’t be studied in fruit flies. For example, I study the immune system, which is key to human health. You know how if you get chickenpox once, you generally don’t get it again? That’s because your immune system has adapted to recognize the chickenpox virus. But the way Drosophila’s immune system adapts is really different from ours and from other mammals. The model I use is Mus musculus, the house mouse. As different as we appear from mice, humans and mice share around 95% of all genes and get most of the same diseases. And like Drosophila, mice are relatively small and easy to keep in the lab. When you throw in all of the many mouse-specific technologies people have developed over past years, it’s not hard to understand why mice are the most commonly used model to study human disease.

William Castle, the scientist Michelle already talked about in Part One, put C. C. Little, a sophomore at Harvard at the time, in charge of his mouse colonies. Little was hooked and turned his collection of pet-fancier mice into genetically identical strains of laboratory mice through breeding. He did this for many of the same reasons other scientists generated in-bred strains in Drosophila: reducing genetic variation allows for the comparison of experimental results across different animals and laboratories. Years later, in 2002, the mouse became the third animal–and the first mammal–to have its entire genome sequenced. This finding made it possible for researchers to plan genetic manipulations in mice for the first time, and scientists have been using mice for intensive genetic studies ever since.

Mashaal So Alex, you mentioned you work on the immune system in mice – what exactly are you doing?

Alex I work on a mouse model for type 1 diabetes, the type of diabetes generally diagnosed in kids and thought to be inherited. In contrast, Type 2 diabetes is generally diagnosed later in life and is associated with obesity. Type 1 diabetes is an autoimmune disease, which means that it’s caused when the immune system attacks and kills cells of its own body. In type 1 diabetes, the immune system attacks the insulin-producing cells in the pancreas. Once the immune system has killed these cells, the person will develop diabetes.

Right now, the best mouse model for type 1 diabetes and actually one of the best mouse models for any human disease, is the nonobese diabetic (NOD) strain of mice. These mice are a well-established model and are easily available from suppliers all over the world. At the Jackson Laboratory in the USA, which was actually founded by C. C. Little, NOD mice cost around 40 dollars per mouse and can be delivered in a few days. The strength of the NOD mouse model is its many similarities to human T1D. As in humans, NOD mice spontaneously develop type-one diabetes. NOD mice generally develop T1D when they’re young adults, around 12 weeks old. In humans, the average age of onset is closer to 14 years, but of course humans live substantially longer than mice. In fact, it’s actually a very unique feature that this mouse model develops T1D spontaneously- many other mouse models of human diseases require a treatment for the mice to become sick.

The NOD mouse model for T1D shares another key trait with human T1D: both are caused by the similar genetic mutations, suggesting the cause of the disease is the same in both mice and humans. Researchers can use this mouse model to study many questions related to T1D.  For example, we can study the development of T1D using younger mice that haven’t yet developed T1D. We can also study the established disease by using only mice that are already sick. Sick mice can easily be identified by measuring urine or blood glucose levels.

Amy What’s it like to work with these mice? Can you walk us through what some of your research looks like?

Alex Sure! Since I’m sure most of you have never performed experiments with laboratory mice I will start all the way at the beginning. In order to get to the mice in the morning you first have to enter the mouse facility, which is actually quite a procedure. The mice used for our experiments are supposed to be held in facilities that are as clean as possible, in order to limit uncontrolled environmental factors that could unknowingly influence the outcome of experiments. This means that everyone entering needs to change their street clothes into clean scrubs and put on shoe and hair covers. Next, you need to go through an air shower, which is basically a small room in which air is blown at you for a few seconds. This helps clear off dust and dirt particles and prevents debris from getting into the clean facility. Once you enter, you go to the room that belongs to your lab and pick out the cage with the mice are you’re planning to use for your experiment.

When working with NOD mice, it’s usually a good idea to check whether a mouse is diabetic before using it for an experiment. This can be done in two ways: measuring the glucose level in the blood or in the pee. To measure the blood levels, you take a mouse out of its cage and place a small cut on its tail using a razor blade. This is actually very similar to the procedure performed with humans at the doctor when the finger is poked with a small needle. You can then measure the glucose levels in a drop of blood using a normal blood glucose meter. If you want to measure the glucose level of the pee, a mouse is picked up so that its belly is facing up. The belly can then be tickled so that the mouse pees. You measure the glucose level of a pee drop with a blood glucose meter, too.

Once you’ve determined the health status of the mouse, you can decide whether you want to use the mouse for the experiment or not. Then there are different experiments that are performed on NOD mice. Some experiments involve some kind of treatment, such as injecting reagents into the body cavity. Usually mice are then sacrificed for analysis a few days after the treatment. Other experiments require the mice to be sacrificed immediately. Laboratory mice are generally euthanized using CO2.

Michelle So do the kinds of things you discover in these NOD mice always apply to humans?

Alex No, not necessarily. Even though humans and mice are similar in many ways, they are still very different species. I don’t know of any prominent cases where findings in NOD mice didn’t apply to humans, but a famous example for a difference between animals and humans with tremendous consequences is the drug Thalidomide. Thalidomide used to be prescribed to pregnant women to treat morning sickness. It was pulled from markets in the early 60’s, about 4 years after it was introduced, because it caused birth defects. This causes some soul searching about why these terrible effects hadn’t been caught with animals studies. A paper from the 60s we found on this subject described how some, but not all studies done on the effects of thalidomide on pregnant mice, rats, and rabbits found an association between the drug and birth defects. The birth defects were the most common and severe in rabbits. In rats and mice, however, even though over twenty studies were done, less than half of those found a significant link between thalidomide and birth defects. Most surprisingly, no connection to birth defects had been observed in primates studies to that date. At least at the time this study was published, why humans and these animals respond so differently was unknown and therefore would have been hard to predict based on prior knowledge. So, findings that are made in mice should still be confirmed in humans or human tissue samples. The good news is that by the time you’ve found something in mice, you know exactly what to look for in humans. In the last few years, researchers have also developed a new strategy to reduce differences between mice and humans – something called “humanized” mice.

Amy Like the mouse in Ratatouille?

Alex Not quite – humanized mice carry functioning human cells (so their immune system is functionally human), so researchers can perform experiments on human cells without needing to do experiments in humans. It’s a pretty great system, because it means that we can do even more to evaluate possible drug treatments before giving them to human patients. But the mice can’t talk or cook.  

Michelle– Regulation of animal research But the idea of “humanizing” animals can apply in other ways, too, especially in acknowledging the fact that animals can also feel things like pain and distress. As Mashaal mentioned earlier, animal sentience hasn’t always been taken as a given, but anti-cruelty laws governing the treatment of lab animals began popping up in Europe and some states in the US in the 1800s. It wasn’t until the mid 20th century, however, that the federal government passed its first law regulating the use of research animals. The impetus for this new legislation came from an unlikely source: an article in Sports Illustrated. In 1965 and 1966, both Sports Illustrated and Life magazines published widely circulated reports of a particularly nasty way of procuring research animals: stealing household pets. The public outcry that followed spurred the passage of a bill that would later be known as the Animal Welfare Act.

Initially, the scope of this law was quite limited. It required both laboratories with animal facilities and animal dealers to register with the US Department of Agriculture, or USDA, but it left the treatment of animals within research facilities to the discretion of researchers. Over time, this oversight was gradually expanded, and by 1970 the USDA was also given the authority to exercise at least some control over the treatment of laboratory animals within research facilities. The number of species covered by the Animal Welfare Act has also been extended over time: the initial formulation of the Act covered only 6 of the most commonly used research animals – dogs, cats, monkeys, guinea pigs, hamsters, and rabbits.

Amy I noticed you didn’t mention mice or rats in that list – were those not included?

Michelle Nope! It’s surprising, isn’t it? And in fact mice and rats are still excluded from the Animal Welfare Act, although it now covers virtually all other vertebrate species used for biomedical research. David Favre, an expert on animal law at the Michigan State College of Law, told me that the omission was primarily caused by lobbying efforts from researchers. There have been a number of lawsuits over the years trying to get the USDA to drop these loopholes, but so far they haven’t stuck.

Most of the time, though, mice and rats are protected by other regulations. And today, animal research is governed by a number of federal, state, and local agencies, in addition to the USDA. Many major research institutions around the world also receive accreditation from AAALAC International, a private, nonprofit agency dedicated to the humane treatment of laboratory animals. In general, however, all of these regulations apply exclusively to vertebrate species, and very little, if any, oversight applies to research on invertebrate animals.

For most institutions today, including academic and non-profit research institutions as well as for-profit pharmaceutical companies, the primary oversight for animal research on vertebrate species comes in the form of an Institutional Animal Care and Use Committee, colloquially known as an IACUC. IACUC’s were formally established by an amendment to the Animal Welfare Act in 1986.  Each research institution has its own IACUC, which is appointed by the institution’s CEO. This committee is required to have at least three members, including a researcher who works with animals, a veterinarian, and a community member who isn’t affiliated with that institution. Before conducting any research on vertebrate animals, researchers must submit detailed proposals to the IACUC for approval.

Amy Alex, have you ever had to work with an IACUC? As a graduate student working with mice, what kinds of trainings or proposals do you have to submit to work with mice?

Alex This is actually interesting to me, too, since I come from Germany and I’ve experienced a very different set of regulations in Europe and the US. In Germany–and elsewhere in Europe–everyone who carries out experiments with animals is required to pass a 40-hour long course from the Federation of Laboratory Animal Science Associations (FELASA). This course includes a theoretical part covering a broad range of topics- from the biology of laboratory animals to the ethics and laws concerning the use of laboratory animals. In addition, it includes a practical part during which every participant has to conduct the most common techniques used in animal research on a living animal in order to prove that they know how to correctly perform the techniques. It’s pretty involved, I have friends who have failed this course the first time around.  In contrast, in the US the required training only includes a theoretical part, which you can usually complete online. This training includes information on animal welfare regulations and basic IACUC policies and standards. Most of the hands-on training comes informally from people in your lab. As for working with the IACUC itself, most of the research proposals submitted to that committee are written by faculty, so graduate students rarely have any direct interactions with the IACUC.

Michelle The criteria IACUCs use for evaluating research proposals are extremely complex (they have separate recommendations for individual species, tailored to the many kinds of research biomedical scientists do), but in their simplest form they can be reduced to the “three Rs”: reduction, replacement, refinement. In other words, wherever possible researchers should strive to reduce the number of animals they use; replace animals with simpler organisms or non-animal research methods; and refine research procedures to reduce pain and suffering of animals as much as possible.

Amy  Wait, can flies feel pain? During our whole fly discussion earlier, it just never entered my mind to ask.

Michelle Ah, that’s a tricky one. I think it’s clear that flies don’t experience pain as intensely as you or I, or even as intensely as a mouse. The whole concept of “replace” in the 3Rs is predicated on the idea that organisms have different levels of sentience, and therefore different levels of pain and suffering.

As for whether flies feel pain… Like I said, it’s tricky, and it’s actually debated in the field. They definitely have nociceptors, which are the sensors for detecting painful events. But pain itself is subjective; in theory, you could respond to events without experiencing the wrenching sensation of hurt that typifies a painful experience. (In fact, there are some human disorders like this, generally termed congenital insensitivity to pain.) But with people, we can identify how painful something is by asking – if you go to the hospital after an injury, they’ll often ask you to rate your level of pain on a scale of 1 to 10.  Obviously we can’t do that with animals, so we usually identify pain behaviorally. If a mouse or a dog hurts its foot, it will start limping. When they experience something painful, they’ll squeal or yelp. Flies don’t do any of that. You can take off their legs, their wings, their entire abdomen, and they’ll keep behaving as if nothing ever happened. That doesn’t necessarily mean they can’t feel pain, and I’m certainly not encouraging anyone to try ripping flies in half or taking off their legs–

Amy Except for the sake of science

Michelle Yeah… but it does limit our ability to come to a conclusion about whether they can or can’t feel pain.  

Still, I find it surprising that there’s no regulation governing the treatment of invertebrate research specimens, at least not in this country. While I do think flies and other simple organisms have at least some kind of sentience and therefore deserve some moral consideration, it seems to be pretty hard to hurt them, as I just explained. But there are other invertebrates that are very intelligent. Octopuses can learn, navigate, and use tools; they play and hide and escape from aquaria in research labs. I find it hard to believe that they’re any less deserving of moral consideration than fish, but research on fish is regulated and research on octopuses isn’t – researchers in this country aren’t even required to use anesthesia if they’re performing a surgery on an octopus. Octopuses were recently added to the list of protected research animals in the EU, though, it’s possible that the laws will change in this country, too.

Amy– Eliminating animal experimentation? The 3R’s have been getting wider purchase in the US recently, and from what I read, that seems to be holding in China too, where animal experimentation is a growing rapidly. Strikingly, however, none of these countries are talking about eliminating animal experimentation all together. As far as I’m concerned eliminating animal experimentation, at least the kind we’ve been focusing on where animals are basically used as model humans would be good. As Alex discussed, there are very real shortcomings to animal models of human disease– they can be expensive, slow and worst of all, inaccurate.

When we started working on this episode, I thought I’d survey new methods that might replace animals in certain contexts and try to estimate how many animals used could eventually be replaced by the methods. That did not work out the way I thought it would. There are so many contexts in which animals are involved in research and many of the methods held up as alternatives to animal experimentation are really complements, not replacements.

Really, working on this episode has only made me more convinced that won’t ever be able to fully replace animals in research. Bodies are too fully interconnected. One day, we might be able to grow a mouse body intact but without sentience. That’s already far in the future, but even with such mice, there are still some studies you’d need to do in a regular mouse model. For example, there are mouse models of PTSD, which would be pretty hard to work with without causing fear or pain.

But there are some examples of methods that can replace animal in some contexts. For example, engineering tissues and growing them in the lab can replace animals. Episkin is one example of such an engineered tissue. It’s a skin model that actually does better than tests on mouse skin at predicting what materials might be corrosive and irritating to human skin. We’re not quite at growing a whole pancreas or liver yet, but my sister actually considered working on a diagnostic tool along these lines as part of her PhD research. Basically, she would have grown tissues from many different human organs and then connected them in an artificial circulatory system.  

Michelle There’s a similar technique that researchers have started using in neuroscience, too. In essence, we can take a small number someone’s cells–say, a bit of skin or blood–and turn them into brain cells. One hope is that this technique might let us study psychiatric diseases by growing brain tissue out of small samples from patients with neurological disorders, like schizophrenia or ALS. Taking even a small sample from someone’s actual brain is substantially riskier and more invasive than drawing a bit of blood, for instance.

The crux of this technique lies in something called induced pluripotent stem cells. Pluripotent stem cells are cells than can be transformed into many different kinds of cells. And they’re “induced,” because we induce regular cells to turn into pluripotent stem cells. In theory, we can use this technology to generate all kinds of cells or organ structures from blood samples or skin cells. For the time being, though, we’re a long way off from being able to make functional organs or to grow a brain in a dish. Still, it’s one of the most promising systems we have for studying human brains without actually studying human brains.

Amy There are also interesting methods that are changing the way people are thinking about animals at least: finding ways to model humans on animals. Did you know that when someone dies after contracting a bacterial infection, it’s generally their own body’s response to the bacteria that ends up being lethal, not the bacteria themselves? So let’s say you’re a biologist, like H. Shaw Warren over at Harvard Medical School, who’d like to study sepsis, this dangerous response our bodies have to bacterial infection. If you turn to mice as a model for humans, you’ll find that the onset of sepsis happens much much later than it does in humans. This difference makes mice a bad model for studying the onset of sepsis in humans. Some scientists have approached the problem by trying to make the mouse respond more like a human in this case.

Mashaal But it sounds like if sepsis happened later in humans, that would actually be a good thing, right?

Amy Right, and trying to make the human immune system act more like a mouse’s is the approach Warren is taking to this problem. He argues that instead of spending time and money to make mice more like humans, to “humanize” the mice, a more efficient approach would be to find ways to temporarily reprogram an infected human’s immune system to respond more like a mouse’s. To really run with this idea, Warren is currently heading up a program called the Species Inspired Research Innovative Treatments.

Mashaal I like that. I read pretty regularly about engineers mimicking biology to make new materials, super strong fibers based on spider webs, super sticky materials based on the physics of how geckos feet are so sticky, but I’ve never thought of  biomimicking to make new therapeutics.

Alex Yeah, I’m also really taken by this inversion of the whole system we’ve been thinking of– trying to make humans model mice rather than the other way around. But you’re not seriously proposing this as a way of decreasing the amount of animal experimentation. Warren and others who take this approach are going to be doing tons of animal experimentation in order to understand their biology well enough that they can come up with methods to import it into humans. And let’s say they come up with a new therapeutic based on how mice avoid sepsis, it’s still not going to be given to humans directly–they’re going to have to find some way of testing it in animals, no?

Amy Yes as far as I can see, you’re totally right about this. The approach is an alternative to trying to make mouse biology more like human biology, but not an alternative to animal testing.

Mashaal– The Future of model organisms Rather than going the direction of phasing out animals models, I think science is really going in the direction of tighter hybrids between animals and humans. Currently, cancer drugs are tested on several well-established human cell lines propagated in the lab, outside of any animals. Personalized treatment for cancer right now might look like sequencing some parts of a tumor’s DNA to find mutations and then providing treatments that are typically effective for cancers with these mutations. But remember how Rebecca was talking about injecting tumor cells into mice? Imagine that when a person has cancer, a sample of their tumor could first be grown up in several mice who then receive cancer treatments. The patient would then only receive the treatments that worked well on their cancer in the mouse. The “humanized” mice Alex mentioned is an advance is making this line of treatment look even more exciting to scientists because the human immune system is an important part of how our bodies respond to cancer. My friends working in cancer really see cancer research and therapy moving in this direction.

Alex Other technologies will make it easier to genetically manipulate animals, making it faster, cheaper and more accurate to use them as models of human disease. For example, newly developed CRISPR technology allows the targeted genetic alteration of almost any animal. In fact, a research article published in 2014 reported the birth of the first monkeys with customized mutations. In the future, this technology could mean that many human diseases will be modeled in monkeys rather than in mice, since monkeys are biologically and genetically much more similar to humans than are mice. However, those biological similarities also raise an ethical problem for working with monkeys, and even though technology will make these kinds of experiments easier and easier, I think it will be important to keep monkey experiments to the smallest possible level.

Amy On the other hand, I’m really interested in seeing how animal experimentation especially on primates develops in China, where many American and European companies are outsourcing their animals testing. Just like outsourcing manufacturing, part of the draw is the lower expense of carrying out the testing there. The quality of life for animals in the testing facilities is also going to be increasing over the next few years– they recently set national guidelines for the care of laboratory animals. At the same time, as the US and Europe cool down research on primates, especially great apes, China is starting to be the scientific hotspot for researchers who want to keep working on these non-human animals and avoid the complex political climate that surrounds that research outside of China. Back when W. Bush was president, he banned federal funding for research on newly created embryonic stem-cell lines because of moral opposition to destroying embryos. Many scientists did not share this ethical concern and furthermore argued that the ban wouldn’t stop embryonic stem cell research, it would just damage American research by pushing it outside of the U.S. While the debate over primate research has not reached the same tenor, I saw several articles and comments voicing this same concern while working on this episode.

Michelle Despite these potential trends, there are good reasons to think that we can limit animal research here without slowing down American science. In 2011, the National Academies of Science released a report on the use of chimpanzees in biomedical research. The report found that advances in non-chimpanzee research has rendered continued work with chimpanzees unnecessary in almost all cases. In the future, maybe the development of non-primate or even non-animal models will mean that we can substantially reduce the number of primates or animals used in research without damaging US scientists or getting in the way of important biomedical research goals. It’s not clear that regulators–at least in this country–will allow primate research to expand with the technology, given the ethical concerns.

Alex Definitely. It will be interesting to see how these laws will change with new the technologies being developed.

Michelle And as we discussed, a lot of the regulations and standards for the ethical use of animals in research has emerged from widespread movements and public discourse, like the animal rights movement or people’s desire to protect their pets. And the debate isn’t over. As new technologies emerge and the landscape of biomedical research shifts, we’ll need to continue reevaluating the moral and legal rules that govern animal research. So if you have an opinion – share it! Cast a ballot, write to your representative, and, of course, leave us a comment! We always love to hear what you think.

Alex Soon, we’ll be back with more: on the possible reproducibility crisis going on in science research now, oceans, urban planning and climate change and many more. In the meantime, we want to hear your thoughts on science and animals; and your suggestions for the podcast. E-mail us at or tweet @SITNBoston. If you liked today’s show, definitely subscribe on iTunes and leave us a review.

Mashaal Positive reviews help others find our podcast and we’ll really grateful for any feedback you share with us. The SITN blog and this episode’s show notes can be found at our website

Until next time….

Could you tell what the mashup at the end said? E-mail us your guess!

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