DAVE DAVIES, HOST:

This is FRESH AIR. I'm Dave Davies in for Terry Gross, who's off this week. Suppose we had the ability to fundamentally alter just about any life form on Earth, rendering a bothersome pest harmless or removing a disease such as Alzheimer's in people. Our guest, writer Michael Specter, says advances in genetic research have taken us to the verge of such godlike powers. His latest article in The New Yorker, "Rewriting The Code Of Life," is about a remarkable gene-editing tool called CRISPR. That's right, I said gene editing.

The technique permits scientists to quickly and precisely alter, delete and rearrange the DNA of nearly any living organism. Specter says there's never been a more powerful biological tool or one with greater potential for benefit and harm. Michael Specter's been a staff writer at The New Yorker since 1998. Before that, he was a national science writer for The Washington Post and a senior foreign correspondent for The New York Times. He's currently a visiting scholar at Stanford University, where he's working on a book about gene editing.

Well, Michael Specter, welcome back to FRESH AIR. In this recent piece in The New Yorker, you take us to the island of Nantucket off of Massachusetts. And you describe this scientist, Kevin Esvelt, who's going to meet with local health officials with a - with an idea for dealing with the problem on the island of Lyme disease. How big of a problem was Lyme disease on Nantucket?

MICHAEL SPECTER: Well, it's a big problem. I think there are as many as 40 percent of the residents who have been infected at one time or another, certainly at least a quarter. And it's a growing problem. It's a growing problem both in incidence and also because climate change has permitted mice, which are the carriers, to exist and thrive in more places than they used to.

DAVIES: Right. Now, everybody who knows about Lyme disease worries about getting it from ticks. The approach here was not to target the ticks, but mice. Explain why.

SPECTER: Well, the main reservoir, the carrier, for Lyme is in fact a mouse called the white-footed mouse. And Esvelt first thought about trying to deal with ticks. It's hard to deal with ticks. There's a lot of them. And he realized that if he could somehow change the genetics of the mice, they - when the ticks bit the mice, they would no longer be infective. And he would essentially break the chain of transmission that exists between mice and ticks and humans. And if he could do that, then you might get bit by a tick and it might be annoying, but it wouldn't convey any illness.

DAVIES: So what was the plan for making the mice resistant or immune to Lyme disease?

SPECTER: He is basically intending to rewrite the DNA of the white-footed mice. And he - there are a couple new tools that allow scientists to think about doing that. The main one is CRISPR, which is an editing technology that allows scientists with remarkable precision and facility to edit genes in the way a word processor would edit words. This has been possible in the past with much more complicated technologies, but not easy and not as successful. The other technology is a thing called gene drive.

And it's an unusual bit of natural history, which is that we all get one gene from each of our parents. And that is - our genetic makeup is a mix of those two. However, there are some genes - we describe them as selfish genes - that have figured out a way to cheat and push themselves through populations at greater than a 50 percent percentage and more than they ought to do. And that's been an interesting phenomenon for a long time. It's gone on for millions of years.

But in the last 50 years, some scientists realized, gee, if you could manipulate those selfish genes, you might be able to change genetics in a - ways that would be useful to us. It wasn't easy to do. In fact, it wasn't possible to do until recently. But then when CRISPR came along, suddenly you had a situation where you could, in fact, manipulate genes with great precision and great success.

DAVIES: OK, let's take these two techniques one at a time and explore them a little bit. CRISPR is the gene-editing tool. The idea is - here is that in this huge, long, complicated DNA, you can isolate the characteristic that is associated with something like Lyme disease. Tell us a little how it works.

SPECTER: CRISPR is actually an ancient bacterial defense system. It's like an immune system for bacteria, which is surprising because for a long time, scientists didn't think bacteria had adaptive immune systems. But in 1987, some Japanese scientists were looking for something in DNA, and they saw this weird group of nucleotides, pieces of DNA. They had no idea what they were doing and what they meant and what their function was. And in a piece they published in The Journal of Bacteriology, the last sentence literally was, and we saw this weird, crazy group of nucleotides, and we have no idea what they're doing there. And that was that. And that was not for a very long time.

And then about 10 years later, some people at a yogurt company, Dannon, in Europe - they're all about bacteria. And they were wondering why some of their bacteria in their yogurt was getting killed so frequently and some weren't. And some scientists there realized that the difference between living and dying was - the bacteria that survived, they had these little, short spaces of DNA. And what they are are palindromes, the same backwards and forwards. And they're nucleotides with little, teeny bits of protein spaced in between them. And still, nobody could figure out what those bits of protein were until a few years later when a biostatistician named Francisco Mojica in Spain decided to do a computer analysis of all the proteins that were known.

And what he found was that those little protein bits were pieces of viruses. From then, things moved somewhat rapidly because what that meant was bacteria were seeing viral invaders, they were chopping them into little bits and incorporating them into their genome, which is something like what we do with a vaccination. And when they're in the genome, they're able to defend against another invasion. This is crazy. I mean, no one ever thought this was possible. But eventually, people realized - scientists realized that if nature could do it, we could do it, and that it was basically a programmable kind of a GPS for our DNA, a molecular-GPS system.

And scientists at Berkeley and overseas - Jennifer Doudna and her colleagues, a woman named Emmanuelle Charpentier - played around with the different pieces of this puzzle. And they figured out a way to program it so it would go exactly where they wanted it to go. And we're talking about - in humans, we're talking about billions of nucleotides. And you can shoot that thing anywhere, and it will search for the genetic match, and it'll stop there and find it. And then it can cut it out, delete it, replace it. It's a remarkable advance.

DAVIES: This is almost science fiction-like. So this has been described as, like, a genetic scalpel. You can somehow find exactly what you want in the DNA of an organism, right?

SPECTER: Yeah, there are two parts of this. It's called CRISPR-Cas9. And the Cas9 part is an enzyme. And enzymes are basically things that cut. And it's a scalpel. It's a molecular scissors. So you put those two things together. You program CRISPR to go where you want. And when it gets there, it cuts the very pieces of DNA you want cut.

It's remarkably precise. It works with great efficiency. There are - it is not 100 percent perfect. We can talk about that. But it's more efficient and more successful than any such tool there had ever been or any that anyone had envisioned.

DAVIES: And so you can program it to go where you want by knowing the genetic characteristics of what you're after, like a disease?

SPECTER: Yeah, I mean, genetic characteristics - and nucleotides - we have billions of nucleotides. And they're these ridiculous lists - CTAGAGAG - you know, just endless variations of four - of the four chemical bases of life. But there are differences.

So you can program it to look for those - that particular sequence just like you would program - you could search through all of Shakespeare to look for the words, to be or not to be. And you can program it to search. And when it finds those exact words, it will stop. And it will cut those words out. And it will put in whatever it is you wish to replace it with.

DAVIES: Wow. And physically, how does this happen? Say with a white-footed mouse, you want to make it immune to Lyme disease. Physically, what happens?

SPECTER: Well, what you would do is you would - there's a vaccine that isn't very effective on humans, but dogs use it. And it works on mice for Lyme. So what Esvelt and his team have been doing is they vaccinate mice and then they study the antibodies. And they take the most protective antibodies - the ones that work the best - and they sequence their DNA. Then they take that DNA and they implant it into the embryo of a mouse egg. And then when that mouse is born, it will be encoded to be protected against Lyme. And if you do that enough, and mice made enough, you spread that through a system.

DAVIES: So you find mice eggs and - what? - you have a needle that inserts the material into the egg?

SPECTER: Yeah, it's basically a needle. It's a very, very small needle. I mean, these things are molecular level and they're remarkable.

DAVIES: Michael Specter is a staff writer for The New Yorker. He's been writing about a gene editing tool which could allow scientists to modify living organisms. We'll continue our conversation in just a moment. This is FRESH AIR.

(SOUNDBITE OF MUSIC)

DAVIES: This is FRESH AIR. And if you're just joining us, we're speaking with Michael Specter. He's a staff writer for The New Yorker. He's working on a book about gene editing technology.

OK, so this is remarkable stuff. I mean, we've talked about it here in the context of making mice on an island immune to Lyme disease so that the ticks don't get it and Lyme doesn't spread. But it obviously has potentially much wider applications. What's the potential here?

SPECTER: Well, the potential is literally limitless. One thing you're seeing is that there are very few labs in the world who work with molecular biology that are not using CRISPR to do research much more rapidly than they've ever done before. But in the real world some of the potential is breathtaking.

And one of the things that people are working hard on is trying to get rid of malaria. Malaria kills a thousand kids a day. It affects 200 million people a year. It is one of the most devastating diseases in human history. And there are several talented scientists who have been able to edit the genes of Anopheles mosquitoes, the ones that carry the malaria parasite, so that they do not transmit malaria. And that would be one of the great achievements of humanity.

DAVIES: Right. And you could do similar things with other diseases, too, like dengue, for example.

SPECTER: Sure.

DAVIES: Yeah.

SPECTER: Dengue, any - almost anything that is transmitted sexually - schistosomiasis, which is blood flukes. It affects hundreds of thousands of people very severely every year in sub-Saharan Africa. That's something that could be altered. We can alter certain genetic illnesses in - even in humans. They're working on HIV.

DAVIES: Right. Now, there was - I think in 2012, there was an effort to introduce genetically modified mosquitoes in Brazil. If I have it - understand this right, which - and it essentially made the males sterile, which would reduce the spread of disease but would do it by - and effectively reducing the mosquito population, right? I mean, there are just going to be fewer of them. This is different, right? This - you still have a mosquito. You just have one that isn't as dangerous.

SPECTER: Well, there's a couple ways of doing this. And one is you could try to eliminate the thing that you hate, certain species of mosquitoes. And when it came to the Brazil experiment that was Aedes aegypti. And most entomologists don't believe we would suffer if we got rid of them. But there are a lot of people out there who are legitimately concerned about the meaning of wiping out a species, which may seem like a great idea today, but we can't really look down the road a thousand years.

So Austin Burt, who's an evolutionary biologist at Imperial College London and has been a leader in all this, in 2003 wrote a piece saying, you know, we could probably use gene drive to eliminate these noxious pests. We could also use it to just alter their behavior so that they don't bite us or don't pass on the bad thing or alter their smell so that they're not attracted to us. And that's what a - that's what he's working on now. That's what a lot of people are working on now.

DAVIES: Wow. So just - it's almost corrective genetic behavior.

SPECTER: Yeah.

DAVIES: The pest is still there, but it's no longer a pest.

SPECTER: Yeah, it's like LASIK or something.

DAVIES: This could apply to, for example, pests for crops, right? You can still have the crops - have the pests in the field, but they don't eat the crops if they're genetically edited.

SPECTER: You could see a situation where pests would be slightly altered and they'd exist in their ecosystem happily. But when they came across corn or wheat or whatever it is they like to eat, they'd just say, ick (ph), we don't want that because our olfactory system has been changed in such a way that it makes us sick, and they move on.

DAVIES: In describing these techniques, you say that there has never been a more powerful biological tool or one with more potential to both improve the world and endanger it. It's intuitively unsettling to us to think that we can alter any life. But let's explore this. What are the ways this can be harmful?

SPECTER: Well, there are a lot of ways. First of all, it ought to be intuitively unsettling. It's a big deal. But I think it's clear that if you are a good enough scientist so that you can edit a mosquito in such a way that it wouldn't transmit something like malaria, you could also edit a mosquito in such a way that it would transmit something really bad.

You could see it becoming a biological weapon. I'm not saying it's the easiest thing, but it's totally doable. And as these technologies become cheaper and more accessible, it would be absolutely foolhardy to pretend that that's - that bioterror or even, maybe more likely, mistakes are not possible.

DAVIES: Right. You write that James Clapper, the director of national intelligence, says that genetic editing is potentially a weapon of mass destruction.

SPECTER: He did say that. And a lot of scientists were appalled that he did. You know, my feeling is if people want to kill you, they're - our modern world has proven that they're very effective at doing so. There are lots of ways to do it. I'm not sure many terrorists would turn to editing genetics. But it's also silly to pretend that it's not possible.

So yeah, it's on the radar, and it's something that worries people. But I think when it comes to all this sort of science-fictiony (ph) stuff, you have to think about two things - what are the possible benefits, and what are the possible risks? Some of these things probably don't have amazing benefits. But I wonder what the risks - what the downside of getting rid of malaria could be that would be worse than actually having malaria. And that's the type of thing, I think, we need to do the math on as a society.

DAVIES: Yeah, you know, it's interesting. You point out that - that the concerns about this weigh differently in audiences in the Western world, in the United States, in some respects than they do in the developing world.

SPECTER: Of course. I mean, we have a standard of ethics, which is usually admirable. And we, first, do no harm. And we don't want to use people as experiments. And we ought not even though there's quite a history of us using minorities and poor people in ways that are appallingly unethical.

However, if you go to Africa - I've been there a lot - and you talk to people who are dying of AIDS, dying of malaria, who've faced these things their entire lives and in the history of their people and you say to them, do you - would you like to roll the dice and try this, not uniformly, but almost always they say, yeah, we want to try it because the alternative is so horrible. We - you know, they just have a higher threshold for trying something risky because the benefit could be so remarkable.

DAVIES: So let's go back to Nantucket where this scientist, Kevin Esvelt, wants to use it as an experiment to introduce genetically-edited mice to defeat Lyme disease on the island. And people are naturally concerned about, you know, meddling with Mother Nature. And you write that he says part of his job is to challenge the ridiculous idea that natural and good are the same thing. What does he mean?

SPECTER: Well, I think we have this enduring myth that there is some thing called nature out there, and it's wonderful and shouldn't be messed with. When it comes to nature, you know, in the last 11,000 years - at some point 11,000 years ago, we stopped wandering the earth. We started having settled agricultural communities. We developed towns and then cities near rivers, and we grew things. And ever since then, everything we've done has been meddling with Mother Nature. We can talk about to what degree. But the idea that somehow things out in nature are great and that if we mess with them the situation will be worse is sophistry.

DAVIES: Yeah. He says, natural selection is heinously immoral.

SPECTER: Well, it is. I mean, the amount of death and cruelty that exists in the natural world is unspeakably huge.

DAVIES: Right. Now, that said, Esvelt understands that people are nervous about embracing this kind of, you know, life-altering technology. And he says, the only way to conduct an experiment that could wipe a species off the earth is with complete transparency. How does he propose to be transparent in Nantucket on this field mice project?

SPECTER: Well, see, this is where I think he and a growing number of scientists of a younger generation - of the millennial generation - are absolutely fascinating and right. He wants everything to be absolutely open. He doesn't want to go into his lab, do stuff and then show up and say, look at this cool stuff we have for you. He's been to Nantucket a bunch. I've been with him. He lays out the possibilities.

And he says, I'm not doing these experiments, even in my lab, if you don't want me to. And I'll come back to you at every stage and say, do you want me to continue? Do you want me to release mice on an uninhabited island to see if it works? Do you want me to do a test?

Because he feels that - and not just Kevin, but lots of people feel this way - these things are way too important for scientists in labs to decide. Society needs to grapple with this and decide what the risks and benefits are and whether they want to go ahead. And the only way you can do that is to make science accessible, make people see what's going on, make them participate in the decisions that they very, very rarely have ever had the opportunity to participate in.

DAVIES: Michael Specter's article in The New Yorker is "Rewriting The Code Of Life." After a break, he'll talk more about the ethical issues raised by gene editing and who will address them. Also, John Powers reviews the new Mike Mills film, "20th Century Women." I'm Dave Davies, and this is FRESH AIR.

(SOUNDBITE OF MUSIC)

DAVIES: This is FRESH AIR. I'm Dave Davies in for Terry Gross, who's off this week. We're speaking with New Yorker staff writer Michael Specter, who's written about new techniques that allow scientists to edit genes and fundamentally alter just about any organism on Earth. His article in The New Yorker about a scientist's proposal to eliminate Lyme disease on the island of Nantucket through gene editing is called "Rewriting The Code Of Life."

One of the concerns is suppose we modify some organism and it has an unintended effect out in the ecosystem. Is there any way to reverse a bad decision? Can you correct a gene edit?

SPECTER: Well, that's the 64,000 - or maybe we should bump that up to $64 billion question. Yes, Esvelt and his colleagues have developed something in its early - called a daisy drive. And what that daisy drive is is basically the genetic equivalent of a multi-stage rocket where you would need all the stages for the whole system to work. If you had one or two of the three stages, then the replication wouldn't work. You'd need them all.

And you could engineer that into any creature or any organism that you're editing so that maybe you do it for 10 generations - which in a mosquito is not a lot - maybe you do it for 100 generations. And then it would stop, and then you could see.

Another thing that a lot of researchers - George Church at Harvard and Esvelt and others - have always said is never do an experiment like this in a lab if you can't undo it. And it shouldn't be that hard. Though it is also true that once you release something into the environment it's in the environment and then you're dealing with some questions that are difficult to answer.

DAVIES: So we're talking about this CRISPR, this gene editing, this remarkable ability to alter species. How is this different from, like, genetically modified crops, which we already know about? They're genetically modified foods we eat.

SPECTER: It's different in the following way - genetically modified corn, for instance, is a crop in which you've taken a bacterium or something from another species and you've put it in the corn gene so that it wards off the attack of a weevil or some sort of pest. It mixes the species in a very specific way. This is a much broader thing because you can do it with any gene anywhere. And when you pair CRISPR with gene drive you can do it in perpetuity. And that's the astonishing thing.

Though CRISPR itself, the idea that you can go anywhere in a genome of billions of genes and change something, is astonishing. George Church, for instance, up at Harvard Medical School - one of the things we always have loved to do is use pig organs for transplants. There are constant shortages of transplant organs.

DAVIES: For transplants to humans you mean, yeah.

SPECTER: Yes. Yes. But we've never been able to do it because we reject them. We reject them for immune reasons and also because the pig organs have viruses, retroviruses, and they would make us sick, and we would die.

George used CRISPR to edit all the viruses out of pig organs, every one. And he used it to change the immune profile so that it looks like we'll be able to grow pig hearts and pig livers and use them as transplant donor possibilities. And that is an astonishing advance.

DAVIES: Right. And thousands of people die waiting for transplants of - what? - livers and kidneys and the like.

SPECTER: Well, I think 20,000 people in America die. And those are just the people on the list. There are lots of people who don't make the list because the medical world doesn't feel like they're good enough bets to live very long. But if this works, that wouldn't be a problem anymore. So I see that as one of the biggest potential near-term upsides of this technology.

DAVIES: And how far are we away from having a workable transplant come off of this?

SPECTER: I think that Church would like to have a primate study going within a year and that that primate study would last a year or so. And if it worked, you're talking - then there's some FDA tests and approvals. I don't think five years is unrealistic. It could possibly be shorter than that.

DAVIES: And I read recently that a - there was a preliminary approval given for the use of this gene editing for a trial with cancer patients. Doesn't...

SPECTER: Yeah.

DAVIES: ...Have FDA approval. Yeah, tell us what's going on there.

SPECTER: Well, one of the things that's going on in science in general when it comes to cancer is trying to use our own cells to treat cancer. Like, we have a lot of immune cells. We have T cells that kill cells. And scientists around the world and particularly in the United States have been trying to use those cells to kill our own tumors. The problem with that has been that they're really good at killing. They kill the tumors, but they also sometimes kill other stuff.

So they're really dangerous and hard to control. But what they've found when using CRISPR - and Carl June in Philadelphia is the leader in this - is that you can very specifically edit cells to focus right in on tumors, get rid of those tumors without getting rid of any of the cells you need because frankly, chemotherapy has always been a situation where we're just poisoning cells. We just hope to poison more bad cells than good cells fast enough so that it doesn't kill us.

This is a very targeted approach. In its early days, it's worked a little. But there's a lot of people who feel this will work a lot in the future and that it will be - just a - to be able to use our own cells would be just a tremendous, breathtaking advance.

DAVIES: Right. And this is awaiting FDA approval. So if I - and again, come back to the most practical level. If I'm one of the patients in this study and I have cancer, what do they do? Do they extract some cells - stem cells from me and then modify them and then inject them back into me?

SPECTER: Yeah, that's exactly what they do. And the thing is with T cells, with some of your own cells, you might be able to extract a very few cells and modify them and have them go right to the tumor. So one of the things that these therapies - and even the gene drive stuff with mosquitoes - what they all promise, to some degree, is incredible, cheap approach to terribly expensive illnesses.

I mean, if you're using the gene drive to alter mosquitoes, you're not using drugs. You're not using vaccines. You're not getting people to come to places they don't usually come to to be treated. With cancer, it's incredibly expensive to do some of these treatments. You could see a way in which it's really very cheap. And that would be as exciting as anything else.

DAVIES: So is CRISPR actually in use in altering either human or other organisms' DNA?

SPECTER: It's in use in almost any important lab that does molecular biology. Everybody uses it. It used to be that if you want to figure out what's causing a cancer, you use mice and you try to create mutations that are like what you think the mutations are in humans. You have to breed the mice. And then you have to cross-breed the mice. And then you have to grow a colony of control mice that don't have those mutations.

And it can literally take years. And with CRISPR, you can just do this stuff in weeks. One graduate student instead of nine can do it. It's literally the most revolutionary aspect of this development, that scientists in laboratories are moving at tremendous speed. And that is promising.

DAVIES: So we have this amazing potential to alter life forms through genetic editing. And many people object. They're troubled by it. Who sorts this out? Who decides whether we go forward and in what ways?

SPECTER: That is an amazingly good question, and I wish I had an answer. I think right now, we're flailing about. The regulatory system - you know, this - there's a silly cliche that all science writers use from Arthur C. Clarke about any sufficiently advanced technology is indistinguishable from magic. It's usually not true. I think it's kind of true here. And magic is hard to regulate (laughter). We are way behind in our ability to regulate biotechnology.

There are a bunch of people on the government level, at institutions like Stanford and Harvard and elsewhere, who are coming together and trying to figure out a way to do it. But it's difficult. It's difficult to decide how you regulate the alteration of the very fundamental of life because that's what we're talking about. And it's something that we need to do. It's something - it's a discussion - I don't know what is a more important discussion for our country or our world to have.

And another thing about the stuff is you can edit mosquitoes, and you can have them fly around. And maybe in Tanzania, they want that. But mosquitoes don't say, oops, I'm at the border of, you know, Kenya. Now I'm going to stop. This is not - this is something the world has to deal with in the same way that the world would have to deal with climate change. And we're not so well-prepared for those things, as I think we've seen with climate change.

DAVIES: Michael Specter is a staff writer for The New Yorker. We will continue our conversation in just a moment. This is FRESH AIR.

(SOUNDBITE OF MUSIC)

DAVIES: This is FRESH AIR, and we're speaking with Michael Specter. He is a staff writer for The New Yorker. He's been writing recently about remarkable advances in genetic modification. He is working on a book about gene editing.

One of the potential uses for the CRISPR gene editing is on human embryos, right?

SPECTER: Yes.

DAVIES: I mean, how does that happen?

SPECTER: How that would happen would be you'd go into an embryo, a sperm or an egg, and you would edit the genes. And then when that baby was born, it would have its genes changed. And those genes would be transmitted through the generations. The problems with that are many. One of them is that almost nothing you could do at this stage with editing genes can't be done in another way with prenatal diagnosis or finding out what the problem is.

But a bigger problem is we don't always know what the long-term effect of changing one gene, even if it's clearly beneficial, is going to be. So there are - nobody seriously is talking about - I mean, there are lots of people talking about it. I don't think there's serious attempts to edit human embryos. At some point, that will change.

At some point, we're going to find out that if you change four genes, you're going to increase somebody's IQ by 14 points. And Mom and Dad are going to want that. And it's going to be very difficult. And if we don't do it here, then there's going to be some other country that does it. And this is something we need to think very seriously about. It's silly to pretend it might not happen.

DAVIES: And again, just on the physical level, how do you genetically edit an embryo?

SPECTER: Well, you can go into an embryo. You can go into a sperm cell or an egg and you can isolate the DNA. We do that all the time.

DAVIES: So are we talking about a fertilized egg in a woman's womb? Is that what we're talking about?

SPECTER: Yes, or before it's in the womb, you can look at it in a dish and then implant it. And you can look at it in a dish. You can see the string of nucleotides. And you can see where there are problems or where there might be problems. And you can decide, gee, if we get rid of this, we'll get rid of cystic fibrosis. Let's do that.

Or you can say, gee, maybe if we change this, the kid will be 6'3" or play cello better or make something up. And those things are not unimaginable and not even that difficult technically to do. I should say that we don't know how to make better cellists or people be taller.

DAVIES: (Laughter) Yet. Yet.

SPECTER: But who knows?

DAVIES: You know, when I asked how we sort this out, you said it's an unanswered question. Are there signposts ahead? Are there moments which may be important? I mean, laws, commissions, U.N. panels - is there some recognized way that this - these issues will be considered?

SPECTER: Well, there's a lot of (laughter) - there are panels everywhere you point a stick these days. The National Academy of Sciences issued a tepid but useful gene drive directive this summer. DARPA, our research agency for the federal government, is working on a thing called Clean Genes, which is a way to try and do this safely. Other governments are doing the same thing.

My own personal view - and I think one of the things that's interesting about the Kevin Esvelt experiment, he said - I quoted him in my piece saying, you know, basically, I just pray that we have something wonderful before we have something terrible. And I think if we are actually able to get rid of Lyme disease - or, even better, malaria - people are going to be so thrilled. It's going to be such an exciting development that their minds are going to be a little more open to the next thing.

And I also feel another thing's happening, which is kids are going to be editing genes in their biology classes pretty soon. So younger people are going to have more facility with this stuff. And they're going to understand it in a way that I don't think their parents do. And they're going to be able to make more informed decisions because right now, a lot of us don't have a clue.

DAVIES: You've got to help me with this. Kids editing genes in their biology class? What do you mean?

SPECTER: Sure. I mean...

DAVIES: In a dish? In a what?

SPECTER: You can buy editing kits online. You can buy viruses and bacteria. You can buy the tools required to edit them. It's not something, like, anyone can do at home. It's often described as super easy. It's not super easy. But it's certainly something a high school biology class could do. And you could sit down and your teacher could say, let's edit this virus. Let's get rid of this thing. I've done it myself in labs while I'm writing this book. You can change one version of a gene and put in another version of the gene. And those things are going to get cheaper and easier to do.

So I think you'll see a lot of kids playing around with fireflies and certain types of worms and making those worms glow green and then glow red. And those things will happen in biology class. And they'll be exciting. And they'll be the modern-day equivalent of dissecting the frog that we all did once upon a time.

DAVIES: You said you edited a gene.

SPECTER: Yeah.

DAVIES: Walk us through that. You started with a substance which you were going to edit. Which was - what? - a bacteria or something in a dish, or...

SPECTER: It was - I did a bacteria. And I did a human gene. There was a particular gene that I was working on.

DAVIES: And it was physically in a dish of some kind or on a slide or something?

SPECTER: Yeah.

DAVIES: Yeah.

SPECTER: It was in a dish, and it was grown in nutrient to keep it active and healthy. You can look on a computer and say, gee, I'd like the Alzheimer's - that Alzheimer's gene. I think I'll order it on the internet from this company. And they'll send it overnight FedEx, and then you have it. And then there it is in the dish. And you can also look - there are a couple of very powerful computer programs that emulate that. And you can see what it is in the computer, and you design a replacement.

There is a variant of a gene called ApoE4. And if you have that, you have a greatly increased risk of getting Alzheimer's. And this is known. It's been known for a long time. And people have tried to figure out ways to deal with it in drugs and what does it mean. So you can look at ApoE4.

And then, lo and behold, there's a very similar variant called ApoE2. That's very rare. But if you have that, you have a dramatically decreased risk of getting Alzheimer's. So what we did is decide let's cut out ApoE4 and replace it with ApoE2 and then take that gene and put it in mice and see if it works.

DAVIES: OK.

SPECTER: And so we were able to do that by designing a very similar gene that had a slight difference.

DAVIES: And how do you design a gene? What does that - what does that mean? Physically, what are you doing when you're designing that gene with the (unintelligible)?

SPECTER: You're sitting a computer, and it's, basically, like ordering shoes at Zappos or something. You're sitting there, and you're looking through stuff. And you see the letters in a row, and you decide how many - you need 22 letters in a row. That's the - that may be the thing you want to get rid of. And then you order that on the internet. And they send that with whatever amendment or change you wish to buy.

DAVIES: And then it's...

SPECTER: It costs 59 cents.

DAVIES: ...Then you take that thing that you've got, the Apo2 (ph).

SPECTER: You program that in with CRISPR, this thing that goes searching around. And you add to CRISPR the Cas9 molecule, which is the scissors. It searches around. It has the scissors. It stops when it finds the thing you search for. Then it whips out the scissors, cuts out the thing you don't want, and it puts in the thing that you've packed in to the cargo.

DAVIES: So it sounds like in this world where there's a lot to be anxious about, you're pretty excited about this.

SPECTER: How can you not be excited about the possibility of getting rid of the worst scourges of humanity? I mean, is there anything more exciting about - than the idea of getting rid of malaria? Do you know how many billions of people have suffered horrible lives as a result of things like that, or cancer? I mean, these things are real possibilities. And if you're not excited about that, I really don't know what you're going to be excited about.

DAVIES: Well, Michael Specter, thanks so much for speaking with us.

SPECTER: My pleasure.

DAVIES: Michael Specter is a staff writer for The New Yorker. His recent piece about gene editing is called "Rewriting The Code Of Life." Coming up, John Powers reviews the new Mike Mills movie, "20th Century Women." This is FRESH AIR. Transcript provided by NPR, Copyright NPR.