Trailblazers Special: Dan Rather interviews Walter Isaacson

Host Walter Isaacson, author of The Code Breaker, gets interviewed by esteemed journalist Dan Rather. The two discuss the impact the gene-editing technology CRISPR is having on science and society.
All Trailblazers Podcasts

In this episode:

  • Meet Dan Rather (0:00)
  • What is CRISPR (2:22)
  • What are the challenges? (8:24)
  • Jennifer Doudna's story (12:38)
  • The delicate balance between science and art (16:44)
  • CRISPR and the Coronavirus (19:26)
  • Takeaways from Walter's book (21:59)

The script is flipped this episode, as esteemed journalist Dan Rather turns the focus on Walter Isaacson. The two talk about Walter’s new book The Code Breaker, all about the history of the gene-editing software, CRISPR.

More about how CRISPR technology will shape science for generations to come.

“CRISPR is something that bacteria have been using for a billion years to detect viruses. And so, it can easily be reconfigured to test for viruses.”

— Walter Isaacson, author of The Code Breaker

Guest List

  • Dan Rather With a famed and storied career that has spanned more than six decades, Dan Rather has been one of the world’s best-known journalists for much of the last half century. He has interviewed every president since Eisenhower and personally covered almost every important dateline of the last 60 years. Rather joined CBS News in 1962. He quickly rose through the ranks, and in 1981 he assumed the position of anchor and managing editor of the CBS Evening News—a post he held for 24 years. His reporting across the network helped to turn 60 Minutes into an institution, launched 48 Hours as an innovative news magazine program, and shaped countless specials and documentaries. Upon leaving CBS, Rather returned to the in-depth reporting he always loved, creating the Emmy Award winning, Dan Rather Reports on HDNet. Now, building upon that foundation, he is president and CEO of News and Guts, an independent production company he founded that specializes in high-quality non-fiction content across a range of traditional and digital distribution channels. Rather’s latest book is New York Times bestseller, What Unites Us: Reflections on Patriotism. A graphic novel version of the book will be released March 9th 2021. Rather’s most recent writing can be found in his online newsletter, Steady on Substack (

Dan Rather: One thing, Walter, I was thinking today, I know that you have a place in the French Quarter. Little known fact, I lived in the French Quarter for a brief time in 1962. I could-

Walter Isaacson: Actually, I’ve walked by there all the time. I’ve never seen the brass plaque that says, “Dan Rather lived here.”

Dan Rather: Hardly.

Walter Isaacson: Hello, I’m Walter Isaacson. And this is Trailblazers from Dell Technologies. I have a special episode for you today. As you might know, the genesis for this show came from my interest in writing about some of the greatest minds and innovators ever to walk the earth. People like Albert Einstein, Ben Franklin, and Leonardo da Vinci. These trailblazers have changed our understanding of the world and impacted the lives of millions of people.

Walter Isaacson: The years I’ve spent researching the accomplishment of these larger-than-life characters has taught me how to spot visionary minds that can take a discovery and turn it into an invention. My new book is about one of those people. The book is called The Code breaker. It’s about a Nobel Prize-winning scientist named Jennifer Doudna who’s at the center of a new scientific revolution that has the potential to change the human species as we know it.

Walter Isaacson: Doudna and her colleagues are harnessing CRISPR gene-editing technology to perform medical miracles. But any technology that has the power to alter our DNA comes with huge moral questions. We’re going to switch things up a bit. In today’s episode, we’re turning the mic on me.

Walter Isaacson: I invited my friend, Dan Rather on the show to discuss CRISPR and my new book. I’m sure you know who Dan is. He’s one of the biggest names in the history of network TV news. He anchored the CBS Evening News team for 24 years and was a regular correspondent on 60 minutes. Recently, he produced a widely acclaimed documentary, all about CRISPR called Human Nature, which you can find on Netflix.

Dan Rather: Walter, always a pleasure to be with you.
Walter Isaacson: Thank you, Dan.

Dan Rather: Let’s talk about the book, your latest book in the Trailblazer series, if you will, is The Code Breaker, which covers the story of CRISPR. Give us a definition of CRISPR.

Walter Isaacson: CRISPR is this wonderful system that bacteria have been using for like a billion years or so, to fight off viruses. And what the bacteria do is they take a snippet like a mugshot of any virus that attacks them and they put it in their DNA so that if those viruses attack again, the bacteria knows how to chop them up. Well, that’s a really cool thing, especially nowadays when we’re trying to fight wave after wave of viruses. But with Jennifer Doudna and others discovered was that you could use this as a tool to edit genes. So, it’s a very simple system that will cut a gene and a human body exactly where we tell it to, all derived from this old system that bacteria have used for a billion years fighting viruses.

Dan Rather: Well, and why write about it? Why a CRISPR and why now?

Walter Isaacson: It is the subject of our time that’s going to demand the most moral clarity of how are we going to use it. You help make a documentary called Human Nature that’s now on Netflix. That’s just about CRISPR and the revolution. And there are people in it. There’s a wonderful kid, David Sanchez, who could be cured of sickle cell anemia. Well, that’s great. That would be a wonderful use of CRISPR. But we have to figure out what if you could edit embryos and reproductive cells so that we could hack the evolution of the human race. We could have kids that were stronger or taller or we could change their personality in the future. That’s something that, ethically, we’re going to have to figure out, “Do we want to do it?”

Walter Isaacson: The best way for society to figure out, “Do we want to do it?” Is to really mean we, meaning you and me, and all of us, should understand the technology. So, by telling the story of how they develop this technology, I hope to demystify it, make it seem really promising, but also make it seem like something we should understand because we’re all going to have to figure out the rules of the road over the next 10, 15 years.

Dan Rather: We’re all going to have to figure out the rules of the road within the next 10 or 15 years. I want to underscore that. And I want to stop for a second and do what we call in television a wide shot, that as so many people know, Walter, that you’re the best-selling author of Leonardo da Vinci. Before that you did Einstein. Now you come back with this account, this story, a great story, a gripping story of how a science Nobel Prize-winner Jennifer Doudna and her colleagues launched a revolution, a scientific revolution.

Dan Rather: Now, as you’ve outlined, this can, it probably will allow us to cure some diseases, maybe many diseases. It’ll allow us to fend off viruses and indeed improve the human species. So, my question to you, Walter, is where does this fit in the great arc of history, the great sweep of history? You’re a historian as well as a first-rate journalist and professor, but in the course of history, where does this fit in?

Walter Isaacson: We’ve had three great innovation revolutions in modern times, and they’re based on the three fundamental particles of our existence, which are the atom, the bit, and the gene. So, the first half of the 20th century, innovation was basically built on the atom and Einstein’s theories at the beginning of the century that lead to the atom bomb, and GPS, and space travel, and semiconductors. Then you have the second half of the 20th century that was based on the bit, meaning a binary digit that can encode all information. And so you get the computer, you get the microchip, you get the internet. And when those are combined, you get a digital revolution. Those were very consequential revolutions, but in the flow of history, this third revolution, which will be the first half of the 21st century is based on the fact that we started this century by being able to sequence the human gene through the Human Genome Project. And now through CRISPR, we’re able to write and rewrite the human genes.

Dan Rather: Well, what can gene editing do for humankind?

Walter Isaacson: Right now, it’s already cured a lot of diseases. And this just in the past couple of years. Eventually, we’ll be able to edit out these single-gene mutations that are so horrible, and that’ll be a great thing: Huntington’s disease, cystic fibrosis, multiple sclerosis, and sickle cell anemia.

Walter Isaacson: The next threshold, and this sounds like science fiction, we’ll be editing reproductive cells so we can produce designer babies. But like all good science fiction, part of it has already turned out to be true. I mean, two years ago, as you well know, Dan, a Chinese scientist created the first designer babies. And they were edited so that they didn’t have the receptor that allows the virus that causes AIDS, the HIV virus.

Walter Isaacson: Now everybody thought, “That’s horrible.” And it was because it was premature. We weren’t ready for this. But now, after this coronavirus pandemic, the idea of editing the species to be less susceptible to viruses seems less of a peril and more of a great possibility. So, I think we have to be open to all the things that this can do.

Dan Rather: Well, having asked what can CRISPR do for humankind, what are the dangers that it represents to humankind?

Walter Isaacson: I think if we start making what are called germline edits, and that means edits to reproductive cells to create new babies in which the edits will be inherited. That has a lot of promise, but I also think it really does open up some dangers. I mean, first of all, if these technologies aren’t free, and I don’t think they will be, we have to worry about, “Well maybe someday, rich people will be able to buy better genes for their kids. They’ll be able to make their kids taller or stronger, or maybe even kick up their IQ, or memory, or mental processing power.” That will not only take the inequality we now have in our society, but it will encode it. If you allowed parents to just choose all the traits of their children, unfortunately, I think we’d edit out some of the diversity in our species.

Walter Isaacson: So, I think CRISPR holds enormous potential. I don’t think we should stop gene editing in using it to fight diseases, but I think we ought to consider the moral implications of using it to enhance our children, especially when it’s not medically necessary. And in the short term, we have to worry about unintended consequences. I mean, it took Mother Nature a million years to weave together the three billion pairs of letters in our DNA. And I think it’s pretty dangerous for us to come along now and say, “Oh, let’s mess with it. Let’s rewrite it.” I think we have to be careful before you fiddle with Mother Nature without worrying about the unintended consequences.

Dan Rather: But who is to decide, Walter? And I don’t mean that question aggressively, but it is an obvious question that, for example, when nuclear power was first conceived and then invented as you outlined so well in your book, Einstein, right away there came the question, “Well, is there any way to control this to keep bad actors from using it?” So I’m, sort of, staggered around this question because it’s hard to bring it down. But in the end, if the leaders of the world said, “Look, CRISPR has great advantages, but again, have disadvantages. We need some control apparatus.” Is that even possible? And if it is, could you have a vision of how it might work?

Walter Isaacson: It’s harder than controlling nuclear weapons. I can not go into the Tulane chemistry, or physics department, or into my basement, and build an atom bomb. But with CRISPR, I went to Jennifer Doudna’s lab in Berkeley and within two days, I had edited human genes. Now don’t worry. We flushed them down the drain with chlorine. So, they didn’t go into the general population, but this is something that’s easier to do. So, it’s going to be harder to limit and to regulate.

Walter Isaacson: And you ask, “Who should decide?” Well, I think we should decide. And by we, as I said, I mean you, and me, and all of the listeners of this podcast, because James Watson, who did the structure of DNA said something that I found a little frightening, which is, “If scientists don’t play God, who will?” Well, I’m not sure I want to leave this to the scientists. I’m not sure I want to leave it to the politician. I want everybody to have a pretty good understanding of what this is, how it works, how it has enormous promise, and some peril. And then we have a conversation where society says, “These are the things we want and don’t want from this. I think we can try to keep this under control.” But let’s make sure in keeping it under control, we don’t stop this. 80% of what comes out of this has enormous promise. It’s of enormous benefit. So, we want to keep this CRISPR technology moving ahead, even as we have this discussion of, “Hey, how do we make sure it doesn’t get out of hand?”

Dan Rather: Walter, among your strengths as an author, is that you’re an exceptional storyteller. And in telling people about CRISPR in this book, one of the techniques you use is to build it around a strong character. Jennifer Doudna, who shared the Nobel Prize for Science because of her work with CRISPR, is the central character of your book. So, let’s talk about Jennifer Doudna. I have my own memories of the first time I met her and walking away saying, “I was just blown away of A, what she had accomplished, and B, what an interesting person she was.” Let’s talk about how did Jennifer Doudna get on this? How did she get involved and how did it develop that she made the breakthrough with CRISPR?

Walter Isaacson: When she was in middle school, Jennifer Doudna came home from school one day and found that her dad had left on her bed a paperback of The Double Helix, James Watson’s book about how he and Francis Crick had discovered the structure of DNA. And when Jennifer read it, she thought it was like a detective story. It was really amazing. And she was struck by a character who’s treated a little bit condescendingly by Watson named Rosalind Franklin, who did the images that helped discover the structure of DNA. And so she says, “I want to be a scientist,” but her school guidance counselor says, “Well, no, girls don’t become scientists.”

Walter Isaacson: But she’s persistent, and she’s also a little bit stubborn, and driven, and ambitious, all of which are good things. And she decided, “Yeah, I’m going to become a scientist.” And so she does, and she becomes a great chemist at Yale. She discovers the structure of RNA, sort of, in an echo of what Rosalind Franklin had helped do. And she discovers how RNA could be the molecule that started life on this planet. RNA is, of course, as we now know, the heart of the vaccines we’re using for coronavirus. It’s the heart of the CRISPR gene-editing technology. Understanding wonderful molecules like that is what became her passion.

Dan Rather: Among the things that struck me with Dr. Doudna, on the one hand, it was very obvious that she has tremendous drive. On the other hand, there’s a modesty and humility about her that makes her achievements and what she’s done all the more attractive. And she’s the ideal character for a book and you’ve developed her quite well in your book, The Code Breaker. How is she similar, or is she similar, to Ben Franklin, or Leonardo da Vinci, or Einstein, all of whom you’ve written about?

Walter Isaacson: Well, I think there’re two great similarities. One, is curiosity. When we were young in our wonder years, we were curious about everything, like, “Why the sky is blue?” And eventually, people knock that out of us by saying, “Quit asking so many questions.” But the thing that impresses me about Ben Franklin, about Jennifer Doudna, about Einstein, is they never outgrew their wonder years. When Ben Franklin is a young kid and he goes to England for the first time, he measures the temperature of the water because he’s trying to figure out the Gulf Stream. But what’s really amazing to me is near age 80, he’s coming back for the last time after five journeys, and he’s still measuring the water and charting the Gulf Stream. Likewise, Jennifer Doudna, wasn’t setting out to invent a gene-editing technology. She was just curious about this phenomena in which you had clustered repeated sequences called CRISPRs in bacteria.

Walter Isaacson: And as she learned more about it, she realized, “Oh, this could be a useful tool.” And I think that’s true with Leonardo da Vinci. He was interested in basic science, but then translating it into tools. And they all did it through curiosity, just asking those questions. The other thing that they share, Leonardo’s the exemplar of it, is they stand at the intersection of the arts and the sciences. They love both humanities and technology. That’s what that drawing of Vitruvian Man, the naked guy doing jumping jacks in the circle and square that Leonardo da Vinci did, it’s supposed to symbolize the notion of the connection of art and science. And for Jennifer Doudna, she loved French. She loved literature. She loved poetry. And so, when she does science, she’s always connecting it to the humanities.

Dan Rather: In terms of helping the human race, there’re many people around the world now using the breakthroughs led by Jennifer Doudna, but in basic terms, what are the dangers that having led in the discovery of CRISPR that our country given the anti-science tone, which has been very clear over the last three or four years in the country that, for example, has China taken the lead? Are they in danger of taking the lead of this technology, which is going to make such a difference in the 21st century? Or are we still clearly, we in the United States of America, still clearly the leader in CRISPR research?

Walter Isaacson: Well, no, China has pulled ahead in many respects, especially the use of CRISPR against cancer, because it’s an important cancer-fighting tool. It can fight anything that has a genetic code and certainly tumors. You can sequence them, figure out their genetic code, and have immunotherapies that are based on CRISPR. And those are already being used in China. So, I’m not sure it’s a danger. It’s a competition. But competition can be a good thing.

Walter Isaacson: These are good uses. If China barrels ahead and figures out how to use this against cancer, that’s actually a good thing, but it should also spur us in the United States to say, “We don’t want to get behind in this biotech revolution, so we’ve got to pick up our game a bit.” I see the great upside of CRISPR is being used in countries around the world, but mainly it’s China and the U.S. that are using CRISPR to fight cancer, fight genetic diseases, fight things like blindness. And hopefully, there’ll be more international cooperation than competition because we’re all on this planet together.

Dan Rather: Are we ever? Well, that leads to the question of, how is CRISPR being used to detect the coronavirus and is it going to lead to treatments in perhaps an even more effective series of vaccines?

Walter Isaacson: Absolutely. And this will be within the next year or so, in fact, some of it is already here. CRISPR, as I said, is something that bacteria have been using for a billion years to detect viruses. And so it can easily be reconfigured into a very simple detection test for viruses. That’s much simpler than the PCR tests, the one that you have to do now with the nasal swabs and it takes at least an hour to get your results. But you could directly detect the DNA or RNA, the genetic material, of a bad virus in the blood and saliva, anything else using CRISPR. So both Feng Zhang at the MIT and Jennifer Doudna at Berkeley have started companies that are to make detection technologies. Feng Zhang’s is called SHERLOCK. And Jennifer Doudna’s is called Mammoth. And they’ve each come up with these home kits where you can just have it on your countertop in your kitchen.

Walter Isaacson: It’s like a home pregnancy test, and you put a little saliva into it, and it’ll tell you, do you have coronavirus. But it can also be programmed to tell you, do you have strep throat, or it can tell you whether you have a bacterial infection. And eventually, it’s like a platform just like when we got home computers, people built applications you could put on those machines. People will build applications on those machines that’ll say, “Okay, we’re going to test your gut microbiome,” or “we’re going to test to see if you have any latent cancer tumors or many other things.”

Walter Isaacson: So, I think this will help bring biology into the home just like the personal computer, but digital technology in the home. And that’s going to be huge. Also, CRISPR can be used to directly kill the virus, which is a little different than a vaccine. A vaccine stimulates your immune system to kill the virus. Well, the human immune system is really good, but is a bit fickle and sometimes, hard to control. And so it’d be easier if we could just have treatments that say, “All right, this thing will come in, and when it sees the virus, it will kill it.” So, that’s the promise over the next year of what CRISPR will do to make sure we don’t have any more virus pandemics.

Dan Rather: Walter Isaacson, the book, The Code Breaker, Jennifer Doudna, CRISPR, and the future of the human race, what do you hope people will take away from this book? Bottom line, you want them to read the book, observe the book, enjoy the book, learn from it. What is your hope for a reader who picks up this book that they’ll take away from it?

Walter Isaacson: Well, first of all, it’s that trait we talked about earlier, which is curiosity. It’s really, really wonderful to understand how something works. And that’s especially true when that something is ourselves. So, I hope it sparks people’s curiosity for how do our bodies work. I hope it is considered almost the way Jennifer Doudna read The Double Helix, which is, “Well, this is an interesting detective story with a whole lot of colorful characters that smuggles in a small dose of science, but also opens up and sparks my curiosity about what we are as a species and what type of world do we want to leave to our children.

Dan Rather: Walter, I wish you good luck and God-speed with The Code Breaker. It’s always great to talk to you. I’ll see you along the trail.

Walter Isaacson: And thank you, Dan, and thank you for what you did with Human Nature. That certainly sparked things. And I guess my hope is people read my book and say, “I’ll watch the documentary.” And I hope your hope is, “I’ll watch the documentary and say, I’ll go read Walter’s book.” But maybe we should package them together sometime in a little box set.

Dan Rather: I’d love it. Well, Walter, I really do wish you good luck with the book. It’s a major accomplishment and stay in touch. And if I can help you in any way, let me know.

Walter Isaacson: We’ll have home and away visits. I love coming to Austin and I hope you love coming back to New Orleans.

Dan Rather: All right. I’ll look forward to seeing you here.

Walter Isaacson: I hope you enjoyed this special episode of Trailblazers from Dell Technologies. I want to thank Dan for coming on the show. It was an honor to be interviewed by such a legendary journalist. To end this episode, I’d like to share a short excerpt from the book.

Walter Isaacson: Jennifer Doudna couldn’t sleep. Berkeley, the university where she was a superstar for her role in inventing the gene-editing technology known as CRISPR had just set down its campus because of the fast-spreading coronavirus pandemic. Against her better judgment, she had driven her son, Andy, a high school senior to the train station so he could go to Fresno for a robot-building competition. Now at 2:00 AM, she roused her husband and insisted they retrieve him before the start of the match when more than 1200 kids would be gathering in an indoor convention center.

Walter Isaacson: They pulled on their clothes, got in the car, found an open gas station and made the three-hour drive. Andy, an only child was not happy to see them, but they convinced him to pack up and come home. As they pulled out of the parking lot, Andy got a text from the team, “Robotics match canceled. All kids to leave immediately.” This was the moment Doudna recalls that she realized her world and the world of science had changed. The government was fumbling its response to COVID. So, it was time for professors and graduate students, clutching their test tubes and raising their pipettes high, to rush into the breach.

Walter Isaacson: If you’d like to learn more about the book, head over to Thanks for listening.