The secrets of our DNA

Introduction to the Episode

0:00What can we learn from history's most powerful people? Join me, Mike Souter, author of NextGen CEO, in History Extra's new podcast series, History's Greatest Leaders, to find out. Listen wherever you get your podcasts.

0:17Insurance isn't one size fits all, and shopping for it shouldn't feel like squeezing into something that just doesn't fit. That's why drivers have enjoyed Progressive's Name Your Price tool for years. With the Name Your Price tool, you tell them what you want to pay, and they show you options that fit your budget. Enough hunting for discounts, trying to calculate rates, and tinkering with coverages. Maybe you're picking out your very first policy, or maybe you're just looking for something that works better for you and your family. Either way, they make it simple to see your options. No guesswork, no surprises.

0:51Ready to see how easy and fun shopping for car insurance can be? Visit Progressive.com and give the Name Your Price tool a try. Take the stress out of shopping, and find coverage that fits your life, on your terms. Progressive Casualty Insurance Company and Affiliates. Price and coverage match limited by state law. LinkedIn is pretty amazing at helping you grow your small business. We cannot stop your new clients from emailing you at 3am. We can help you sell, market, and hire in one place.

1:23We cannot help you be in three places at once. And while we can't help you organize your calendar, LinkedIn can help you land more clients so you have a calendar to organize. Grow your small business on LinkedIn. Learn more at linkedin.com slash smallbusiness.

Writing the Secrets of Our DNA

1:40What can DNA tell us about who we are and where we came from? In today's episode of the History Extra podcast, Professor Chiri King, who you may remember appeared on the podcast back in November 2025 to discuss her research into Adolf Hitler's DNA, returns to talk about her new book on modern genetics and its role in solving some of history's biggest mysteries. Speaking to John Borkham, Chiri explores the unlikely origins of DNA fingerprinting

2:13and her role in the groundbreaking discovery of King Richard III. Chiri, welcome back to the History Extra podcast. Thank you for having me. So this time we're here to talk about your new book, The Secrets of Our DNA, which is a really comprehensive guide to modern genetics and its uses. But crucially, it's also one that's really accessible and really enjoyable too. What made you want to write it and why now? Well, so obviously over the last few years, and particularly during my PhD, which was basically genetic genealogy,

2:46and what happened was I started getting people contacting me with questions about genetics. And I would write these rather long and involved responses to people about, you know, how our DNA works and trying to answer their question. And over the years, I just found I was doing this loads and loads. And then I actually got approached by a publisher saying, you know, would you be interested in writing a book? So I started kind of getting thoughts together. I ended up chatting to a friend of mine, Sue Black, who a very famous forensic anthropologist,

3:16and she put me in touch with her literary agent. We got chatting about, you know, what would this book look like? And what would I cover? So a lot of it is around questions that I have been asked in cases that I've been involved with. But I also have little sections on things where genetics is going and where there's quite controversial issues that I think the public needs to be involved in the conversation with. And one thing I really like about the book is just how autobiographical it is, like your voice really comes through it. And you talk about your family, you talk about your childhood in Canada,

3:47and your own route into the field. Just for the benefit of listeners, how did you first end up going down this path?

From Medicine to Archaeology

3:54So I started off, I thought I was going to be a medic. And I was in Canada doing the kind of prerequisite courses for eventually going to grad school and becoming a medic. And I was doing calculus 100 or whatever it was, and it was awful. And I just scraped through. It was just awful. And it was with one of my oldest friends, Scott, and he had also done it. And I also just scraped through and we're like, we're not doing that again. So we thought, what are we going to do for second semester?

4:25So we were looking through kind of like the course catalogue. And, you know, Indiana Jones was relatively fresh in our memories type thing. So we're like, yeah, let's do archaeology 101 type thing. So did that on a bit of a whim and got hooked. And I ended up doing archaeology. And I got to go on excavations in Greece. And I came over here. And I thought, well, if I do a degree here, it's three years. If I go home and finish the one in Canada, it's two years. I might as well apply to Cambridge. So I did on a bit of a whim and got in. And I did archaeology and anthropology at Cambridge.

4:57And it was there that I was sitting in a lecture. And it was being given by a lady called Erika Hegelberg. And she had been involved in the Romanov case. And this is this amazing case. So this is Sarge Nicholas and his wife and their five children and four of their household members, like a cook and a valet and a maid and so on. And during the Bolshevik Revolution, Sar Nicholas abdicates. And they are taken and they are kept in a house in Yekaterinburg.

5:27And eventually, they are really brutally murdered. And their remains are hidden somewhere near Yekaterinburg. And they are decades later found. And it was a question of how do they answer whether or not these remains are the Romanov family. And they did that through a combination of osteology, so examining the bones. But also, this was the early days of DNA fingerprinting. And they did DNA fingerprinting, worked out that this was a family. They used a piece of mitochondrial DNA, which is passed down through the female line.

6:00The Tsarina was related to Prince Philip, so he gave his DNA. And it was just this amazing combination of history and archaeology and osteology and genetics. And it was one of the very first cases. And I was just, that was it. That's what I want to do. So I asked around my tutors at Cambridge and they all said, well, one of the best places to go is Leicester, University of Leicester. Professor Sir Alex Jeffries is there, inventor of DNA fingerprinting. So that's what I did. I ended up going and doing genetics at Leicester. So we did a slightly kind of circuitous route to get there. Yes.

The First DNA Fingerprinting Cases

6:31And so if we move from the Russian Revolution to mid-1980s Leicester, because that's when Professor Sir Alex Jeffries kind of made his name with a particular case. Yeah, yeah. So he basically discovered DNA fingerprinting. And it was this ability to tell people apart using their DNA. And this was absolutely revolutionary. And one of the things I go into, this is chapter one, is about sort of identification. And actually, the first case was not a forensic case.

7:05So most people, DNA fingerprinting, they think, you know, it's the police sirens and they take DNA from the crime scene and out pops and we know who the person is. And it was used for that. But actually, the first case was actually an immigration case that it was used for. And I go into the background about this case. This was a young lad who had been living in Ghana with his father. His mom lived here with three of his siblings. And he came back from staying with his dad in Ghana. And the home office didn't believe it was actually her son, Christiana's son.

7:36So they thought that Andrew might be a nephew or something. And they were able to do the DNA fingerprinting case and prove that he was actually her son. So it was this incredibly emotional case because you can well imagine, you know, there's a mom, her son, they're threatening to deport him. She's got three of her children here. And that worry and, you know, trying to kind of prove who he was. And here, DNA was able to do it and reunite a family. So it's this incredibly emotional case. And the lovely thing I like about it is that even everything that it's been used for since then,

8:10the forensic cases, it's the one that Alec is most proud of to this day. And I think that's a really, really kind of sweet story. And then, of course, I go into, you know, how it's used in forensic cases and how it's really changed the world. And one of the things I chat about at the end is that, you know, he's won most of the biggest scientific prizes there is. But the one thing that Alec Jeffries has never won is the Nobel Prize. And I've always been a little bit surprised by that. And you maintain that friendship now. I think you say in the book that you still phone him up. You still talk to him about to get his advice.

8:41Yeah, yeah.

Unearthing King Richard III

8:42So the University of Leicester has obviously played a big role in your life, Turi. I think most people will know you for the discovery of Richard III, a.k.a. the King of the Car Park. For those listeners who might need a bit of a refresher, how did you first become involved in that project? So I got an email from Richard Buckley, who was co-director of the University of Leicester Archaeological Services. And this is June 2011. And he writes to me.

9:13He has been contacted by a lady called Philippa Langley, who was part of the Richard III Society. And she wanted to see if she could get an excavation going. But obviously, she doesn't have the expertise to lead that. We need archaeologists and geneticists and, you know, osteologists and all of these kind of people. So, you know, to be able to actually get the permissions to do it and things like this, you know, has to be done through a sort of a recognized body. So Richard Buckley, co-director of the University of Leicester Archaeological Services, emails me and he knew I had a background in archaeology and that I'd moved into genetics.

9:46Sir Alec Jeffries was no longer working in this area, but I had been starting to work in this area. And it was basically an email that said, you know, we're going to be looking for the remains of somebody who's quite famous, who is buried in downtown Leicester. And I can't tell you who it is. And I wrote back, is this Richard III? Because I knew about Richard III supposedly being buried in downtown Leicester. Because when I first arrived in this country, my aunt, my auntie Lynn, who was really interested in Richard III, took me to Bosworth Battlefield, lent me books on him.

10:16So I had already known for some 20 odd years that he was supposed to be buried in downtown Leicester. And Philippa wasn't the first person to try and get an excavation going. So there was a lady called Audrey Strange from the Richard III Society, who in the 1960s tried to get an excavation going. You know, there have been papers and newspaper articles over the years that, you know, he's supposed to be in this, kind of buried in this area of downtown Leicester, where the Greyfriars Friars used to be. So he's killed in battle at the Battle of Bosworth, brought back. We know from historical documentation that he is buried in the choir of the Church of the Greyfriars in Leicester.

10:49Since then, they've had the dissolution of the monasteries. There's kind of one sensational source which talks about him being dug up during the dissolution of the monasteries and thrown into the local River Soar. But there'd been academic scholarship that had said, no, he's probably still here somewhere. So, yeah, basically, the idea was that we would do this excavation in downtown Leicester in the area of the Friary Precinct. And that started in August of 2012. And I had been brought on a year earlier to lead on doing the excavation in what's known as clean conditions.

11:20So this is where you wear the full-on, you know, face mask and gloves and all that kind of CSI suit type thing. Whilst you're doing the excavation, because the DNA that would be in any remains of interest are going to be very, very damaged and not much left if there's anything in there. And all we need to do is breathe on the remains and we're putting our DNA on it. So we're digging under what's known as clean conditions. And then to lead on the sort of the genetic and statistical analysis of like, you know, is this actually the remains of Richard if we found anything? And we start the excavation and six hours, 34 minutes in, Matthew Morris, our site director, you know, this, the people think the archaeology is really straightforward.

11:57It's not. You're looking for like minute soil patterns and this kind of thing. And he spots a little bit of bone that the digger has brought up. So he hops into the trench and he goes, yeah, I think there's a little, there's an articulated skeleton under here, a skeleton that's under this thing. But we've already budgeted into the budget. We're going to lift up to six sets of remains, but we're not going to do the first six we find because we have to make educated and ethical decisions about which sets of remains are we actually going to uncover and lift.

12:29So we're just started excavating. We don't know where we are. We know Richard's supposed to be in the choir of the church of the Greyfriars. We don't even know if we found the friary at this point. So we keep excavating for about two weeks to sort of get a map as to where we might be. And then we realize, okay, where that skeleton was found on the very first day, that looks like it's down in the choir. We've now found enough bits of the friary to go, that looks like it's down at one end of the choir. So let's make that skeleton number one. We will uncover that. And Joe and I, Joe is our osteologist, and I start excavating.

13:02And we are kind of going from the legs up and we get up to sort of towards his hips. And Philip has brought in a film crew. So Channel 4 is doing a documentary. And I work with film crews a lot and they're lovely, but they do often get you to do things, you know, again, and can you cover that up? And Joe and I were getting a little bit worried that we wouldn't be able to uncover and lift the skeleton all in one day. So we stopped excavating and I had to go off to a conference, a forensics conference in Innsbruck the next day. So I'm not going to be helping with the rest of the excavation of the skeleton.

13:35But jokingly, as I scamper out off the site, I'm like, oh, yeah, but I won't miss anything. That's probably a 90-year-old friar who lived a nice long life and died in his bed. I won't miss anything exciting tomorrow when you finish uncovering this. So, of course, Joe finishes uncovering and we have a youngish male with severe battle injuries with a very strong curvature to the spine. We know that Richard died in battle. We know he's age 32 when he died. And there has been sort of historical documentation talking about one shoulder being higher than the other.

14:07Shakespeare paints him as a bunched back toad. So we have to take that carefully because Shakespeare's writing during the Tudor period. But then this is when the really hard work starts because now we have to do all of the analysis to determine whether or not these are his remains. So this is where you've got experts coming in from all different areas. So stable isotope, radiocarbon dating, genetics, osteology, forensics, wound analysis. It was this really lovely, huge project that no one person could have done on their own. It required the expertise of people who were academics, non-academics, all bringing their expertise to the table to make it the really successful project that it was.

14:46And that's the thing that I really love about the Richard III project is just how many people were involved and just what a great team effort it was. And Turi, of course, this is covered extensively elsewhere and listeners can go and read the book. But in terms of the testing that you did, in the most basic sense possible, this was centred on the mitochondrial DNA, wasn't it?

Testing the Royal Remains

15:07Yeah, yeah.

Testing the Royal Remains

15:08So the DNA that Richard had inherited from his mother and which was shared by female-aligned descendants of his sister. Yeah, yeah. So through his sister. So there's the vast majority of our DNA is a very complex mixture of that, of our ancestors. But there are two pieces of DNA that are passed down in a really simple way down through the generations. The first of these is mitochondrial DNA. So this is a small circular piece of DNA that's in the egg. And so Richard would have inherited it from his mom, Cecily, who also gave it to his sister, Anne of York. And there had been a female line relative that had already been traced by a chap called John Ashton Hill.

15:41But some of the issues there was there wasn't any of the documentary evidence to prove that tree was correct. So what the university did was had a team that went back and went through and just double-checked, pulled out all the documentary evidence to prove that was correct. That was really important to me because if there wasn't a DNA match, how do we know it's not because the tree is wrong? So we had to really make sure that that was correct. And while doing that, they found somebody else. So we had two female line relatives who were 14th cousin twice removed from each other. And if you look at their mitochondrial DNA, one had one tiny genetic mutational difference, not something to worry about.

16:16And they matched the skeleton. So that was amazing. The Y chromosome comes down through the male line. So what happened was it's actually quite easy to find male line relatives. So you go to Burke's Peerage. We found male line relatives who agreed to take part in the project. They didn't match the skeleton. Now, I was not remotely worried about this because my PhD had been on the link between surnames and the Y chromosome. And I knew that sometimes what happens is that the Y chromosome that a man gets is not from the guy who's enlisted in the family tree.

16:47It's from somebody else. So you are going to get what's known as a false paternity. The biological father is not the one that you think it is. So I knew that this was a possibility coming up. And one of the things that's really important about the Richard III case is it's not just the DNA. It's all of the strands of evidence, just like any missing person's case. If you went missing, they wouldn't go, we found the first person with brown hair. Oh, that's him. You're bringing all of the evidence together. What was he wearing? Where was he? All this kind of stuff. We do the same thing with Richard. We kept some information out because it was circular and would bias towards it being Richard.

17:21So, for example, the stable isotope analysis was showing that he had a high-status diet. But he's buried in a high-status part of the church. So that starts to become circular and it's biasing it towards it being Richard. So we kept that out. But basically, when you bring all of the other strands of evidence together and you do a Bayesian statistical analysis to get a likelihood of, is this him versus somebody who looks like they've got all the characteristics of him, it's not him, that gives you a likelihood ratio of 6.7 million to one in favor of this being Richard versus somebody purely by chance.

17:51So, yeah, so it was a very, very big undertaking of which DNA was a part of it. Insurance isn't one-size-fits-all. And shopping for it shouldn't feel like squeezing into something that just doesn't fit. That's why drivers have enjoyed Progressive's Name Your Price tool for years. With the Name Your Price tool, you tell them what you want to pay, and they show you options that fit your budget. Enough hunting for discounts, trying to calculate rates, and tinkering with coverages.

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18:53LinkedIn is pretty amazing at helping you grow your small business. We cannot make your email response time faster. We can help you sell, market, and hire in one place. We cannot help you find space for your three desk drinks. Why do you have three? And while we can't help you find the perfect volume for your presentation video, LinkedIn can help you find the perfect audience for your business. Grow your small business on LinkedIn. Learn more at linkedin.com slash smallbusiness.

19:23Hey, I like your new RAV4. Thanks, yours too. What does RAV stand for anyway? To me, it's the Remarkably Advanced Vehicle. Really? To me, it's the Runway Approved Vehicle for its amazing style. What about Remarkably Adaptable Vehicle because of its versatile cargo space? Or Really Admired Vehicle. Oh, or Really Awesome Vehicle. It really is the Recreational Activity Vehicle. The stylish 2026 Toyota RAV4 Limited. What's your RAV4? Why do you think this discovery resonated so strongly with the public?

19:59I think it's this big historical mystery. It's been one of the biggest mysteries. So we knew that Richard was killed at the Battle of Bosworth. We know there's historical documentation that talks about him being buried in the choir of the Church of the Grave Fires. The Grave Fires has now been torn down. So where is he? His grave. The precise location of his grave has been lost. We always knew where the Friary Precinct was. And you have a pretty good idea that, you know, the Friaries are going to be close to main roads. I mean, this is where Richard Buckley's expertise is great because he's been excavating in Friaries in downtown Leicester before, done maps and all of this kind of stuff.

20:33So it was this whole thing about, well, where is he? He's gone missing. He's one of the few kings where we don't know where his remains are. And I think it's that lovely kind of combination of, you know, historical hints and then the forensics and the genetics and doing the excavation that we find him on the very first day, but we don't realise that it's him and all of that kind of stuff. I think there's something for everybody in that story. And I think that's why people are still so interested in it.

Genetic Genealogy and Family Secrets

21:00Terry, what impact did the case have on genetic genealogy overall and people ordering consumer DNA testing kits? Yeah, so direct-to-consumer DNA testing kits had started at about 2000. And this is where I used to get people calling me up and saying, could you do my DNA? Because I was doing this PhD project on the link between surnames and the Y chromosome. So rather than going through that route, if I would do their DNA testing for them, they were getting it done for free. I mean, obviously, since Richard's mitochondrial DNA and Y chromosome type have been done, I get loads, oh my goodness, so many people emailing me saying, can you do my DNA and see if I'm related to Richard III?

21:36And genetic genealogy has become this absolutely massive, massive thing. So it's been companies like Ancestry and 23andMe, which came along that little bit later, where for a relatively small amount of money, you can, you know, spit into a tube and send your DNA off and get your results back. And I think it's been absolutely massive. And that brought me into the television program, DNA Family Secrets, which I do with Stacey Dooley, where I use DNA to help people trace ancestry relatives, particularly for people who are, you know, if they're adopted or they're donor conceived or they don't know who their father is.

22:11Or increasingly what's happening is people take a DNA test and they realize that their biological father is not the father they thought it was. And it can be an incredibly moving and powerful thing to be, I suppose they allow us to come on their kind of journey with them and let us be part of this, finding out the results. And I feel sort of hugely privileged to be a part of it. And it's incredibly powerful and emotional what DNA can do for people. Yeah, because identity is such a big part of this, isn't it? Oh, huge.

Yeah, and I think that's one of the things that I've chatted about this before in that with the program, when I'm giving people their results back and I am saying, we have managed to find your father or your mother or your sibling or whatever, you can almost see kind of who they are sort of shifts almost in front of you.

23:02It is like they are really processing like where they fit in the world and it is really a big moment for them and it takes them time to kind of digest that kind of thing. And one of the things that we have done on DNA Family Secrets is we show the reality of DNA testing. So sometimes it's not possible to answer the entirety of the question. So, for example, people might come and go, you know, I don't know what my ancestry is. We can do that fairly quickly, but things like we don't know who my father is, that might be harder to do if the people aren't on the databases just yet.

23:34And I say to them, look, these databases are growing all the time. It might be six months, a year, two years, and somebody will pop up on the database and we can answer your question. That was something that happened with Matthew. So Matthew came to us. He knew who his mom was. He'd been adopted. He had been told his dad was Jamaican. And when we did the DNA results and I'm looking where he's getting his DNA matches, he's from the Seychelles, but the matches weren't there to be able to tell him who his father was. So in the program, we do the filming and I say, look, I can tell you you're from the Seychelles.

24:06And that's a really big moment for him. And I was like, well, you know, can't say who your father is just yet. Getting matches to particular surnames, particular families, but haven't been able to connect the trees yet. And then just before the program went out, someone popped up on the database and it helped me find his half-brother. So Matthew's half-brother, Carl, and oh my goodness, they look so similar. And then from that, he didn't know who his father was. And then from that, eventually we were able to trace who his father was. So sometimes it happens after the program is finished.

24:38And I think that's a really important thing to show on the television program is that sometimes you can't answer absolutely everything all at once. And sometimes it might be later down the line that you can give somebody the fuller things. Because I think people give DNA a bit of an aura, like I do this and I'm going to be able to know this. And not always. And I think that's, I hope that's something that comes out in the book is not just how powerful DNA is, but also some of the limitations of it. What are the biggest misconceptions that people have then? Because I think there are a few phrases, Thierry, that make you wince slightly.

25:10Yeah, there are. Well, so, I mean, I have, one of the projects that I did was when I was looking at the genetic legacy of the Vikings in the north of England. I would have people calling me, men calling me, I'm saying, I think I am a Viking. And I used to love the use of the present tense because the Vikings are a thousand years ago. But they wanted their DNA to prove that. And I had to explain about, look, the way our DNA is inherited, it's a very complex mixture of just some of our many ancestors.

25:41And, you know, I can look at particular bits of your DNA. So, for example, the Y chromosome, to see if it's one that's found at high frequency in Norway, for example. It doesn't mean that that's how it came to be in your family. It wasn't necessarily a Viking who came over. It could have been before or after the Vikings. It's not just found in Norway. It could have been through another route. But then I would say to people, look, if you think about it, you've got two parents, four grandparents, eight great-grandparents. If you go back to the time of the Vikings, the number of putative ancestors that you had at the time was more than the population of the world. So you will have Viking ancestry somewhere in your family tree.

26:15If you're a European, you will almost certainly have Viking. You will have Viking ancestry somewhere in your family tree. But it was that feeling that, but I want the DNA, the badge to sort of prove it, that I can kind of say that this is in my DNA. And I found that kind of a really interesting thing and having to kind of explain that DNA can't answer that question for you necessarily. So that's been one of the ones. I get loads and loads of people who email me saying they think they're related to Richard III. And I have to kind of go, oh, we're all related to Richard III.

26:46We're all related to each other. And that, you know, you won't necessarily be able to find a genetic match unless you're related in particular ways. And here's where a really well-documented genealogy would probably be your better route. And then it's, you know, it's about explaining about sometimes you will be related to Richard III, but the records might not be there to be able to connect you up there. So I suppose it's this idea that DNA can kind of prove everything and it can't. It can't help you for some things. And, Thierry, the notion of identity using identity in inverted commas there can also be quite troubling sometimes, can't it?

Eugenics and Modern Misconceptions

27:21Because one of the darker sections of your book deals with the history of eugenics. Yes. Why is understanding that history so important for understanding genetics today? I go into this because I talk about the Hitler case that I was involved in. And some aspects of his DNA is pretty clear. You know, he has a particular genetic mutation. Looking at his DNA, I cannot tell you how that would have manifested itself in him. But we know that it affects certain things. So the biggest thing that came out of it was that we found out that he had a deletion in a gene known as Proc 2.

27:55And that is something that's involved in genital development. I cannot, from the DNA, tell you what his genitals look like. But we've got historical information which, you know, talks about him having an undescended testicle. And this is something which is a gnome associated with this particular genetic variant. But there's other aspects that we looked at. And these were things like polygenic scores. And it's looking at genetic predisposition towards. And the way people do polygenic scores is they take a bunch of individuals with a particular condition and they look at the genetic variants that they have, maybe at higher frequencies or that they have that people over here who don't have that condition, they don't have it or at lower frequencies.

28:33And then you can take an individual and put them on that spectrum. And when we did that, Hitler came up at the top for schizophrenia, bipolar and autism. And one of the things that we were very careful to say is that this is not diagnostic. This is a genetic predisposition towards. We have to be very careful with this. You know, this is not to say that, you know, he didn't do this on his own. There were loads of people who helped him. This is not to say that people with these conditions go on to commit these sorts of things.

29:03They're more likely to be on the receiving end of violence. So it was about really trying to get the nuance across about what DNA can and cannot tell you from looking at somebody's DNA. And part of what I go into is the fact that we have things now called pre-implantation diagnostics where you can do screening. So, for example, if you know you have a really serious genetic disease in your family and you want to have a family yourself and what you can do is you can screen embryos to select. For ones that don't have that particular genetic variant that might cause a very serious disease that I completely understand, because the idea behind that is to relieve suffering and that I completely understand.

29:44But where it's getting murky is where there are companies, for example, in the U.S. who will say, oh, well, we'll screen for, you know, it's eye color and intelligence. And the fact is, is that intelligence is like most things is a combination of not only your genetics, but all kinds of things like your upbringing and what you were fed and what were your parents like and what was your schooling like. And there's too much environment in there to be able to look at somebody's DNA and say something about what their intelligence is going to be like in a safe way.

30:18And also for selecting for variants that we think might be associated with, you know, higher intelligence, however you measure that, might also be selecting for things that you don't want. We did. There's still so much that we don't understand about our DNA. And I think that we have to be very careful about what we're using it for and educating people about what we can say and what we can't say. Indeed. And focusing on the Hitler's DNA story. So for context, you fronted a two part series with a historian called Alex Kay for Channel 4, and this made headlines all around the world.

30:55What did you learn from the experience of it becoming a major news story? Yeah, well, I suppose I'd had really good practice with Richard III because I'd been through that. And that was incredibly stressful thing to go through. It was, you know, not something that any of us, any of us academics were used to at all. And suddenly going through all of that and the interest in that. So I think when we started the project, we really had no idea what we were going to find in his DNA. For example, I kind of thought, well, are we going to find that he's slightly genetically predisposed towards heart disease or something?

31:26But then the results start coming back and there's some really striking results coming back in there. And it was thinking carefully about how we're going to discuss this, you know, what we can say and what we can't say about it. When the results started coming back, of course, we thought, OK, we know where the press is likely to go with this one. And how can we make sure that we are getting that story out properly and properly mediated with it? Yeah.

31:57So it was an interesting one. It still rumbles on now. And again, listeners can check out the podcast that you did last year with Alex and also read a great feature on our website about that too. Tiri, looking back across all the stories that you cover in the book, which one still amazes you the most? Oh, gosh. People ask me this like, I don't know. They're all amazing. I mean, so I love all of them. I think that early one with Alec, I find really touching. The one about how he's able to reunite a family.

32:27I think that's really good. Some of the stuff that I go into is miscarriages of justice. So like the Amanda Knox, the Meredith Kircher, Amanda Knox case, and just about how the DNA, the CSI effect came in. And people thought that DNA could answer questions that it really couldn't. And it was taken out of context. And these people were in jail for several years as a basis of that. So, yeah, there's loads. That's how I kind of told it, because I suppose that was the way I learned about genetics was I had to. I came at it from being an archaeologist and then moving into genetics.

33:00I was learning it quite quickly. And the thing that got me into it was the stories. So I try and tell lots of stories in the book and how DNA has been used as part of the key to answering that. And is there a historical mystery that you'd love to be able to solve?

The Princes in the Tower

33:16Well, I can tell you the one that I usually get asked about, and that is the princes in the tower. So it is my number one question that I get if I ever give a talk. So for those who don't know the background, so this is Edward IV, King of England. He dies relatively young, leaving two sons. Now, Edward IV is the brother of Richard III, and he has two sons, also called Edward and Richard, just to really confuse things when you're reading about this. Now, when Edward IV dies, the idea is that his eldest son will become Edward V.

33:51And in a sort of intervening period, Richard III comes to the throne, and it's all in slightly unusual circumstances. And the boys slowly disappear from view, and it has been this big question about what happened to them, and all sorts of stories on various sides, including that Richard had them killed. And so what happens is in the 17th century, they're doing renovations in the Tower of London, where the boys have last been seen. And they are putting stuff up on a spoil heap, including skeletons.

34:24And somebody goes, oh, look, skeletons. And they start to think, is this the princes in the tower? They're kind of gathered up with chicken bones and all sorts. And they're kept in somebody's cupboard for four years. And then they're interred in Westminster Abbey in an urn. In the 1930s, there was a study done on the bones. But if you, as a scientist, as you read the study, by about, I think it's from around like the fifth paragraph, they start calling the remains Edward and Richard. They have decided it's the princes in the tower.

34:55Without having done a kind of really proper study. And these days, of course, we could do a very calm, measured, holistic study where you remove the bones from the urn, you lay them out, you look to see whether or not osteologically this fits with them being boys of that age. And then the first test I've always said you would do, because you're trying to minimize any destructive testing here, because these are human remains. And you want to keep that to a minimum. So the first thing you would do is radiocarbon dating, because it could easily be that these

35:26skeletons are significantly older. And, you know, possibly, you know, what if they're Roman or Anglo-Saxon? If they come back as that period, you stop right there, because it can't possibly be the princes in the tower. And there's no point in doing any more destructive analysis to answer this question. But with each stage, you know, you could do stable isotope, you could do genetic analysis, you could see if consistently this is coming back as being consistent with the princes in the tower. We've got Richard III's DNA, we can do this kind of thing now. But you have to get the permission of the Dean of Westminster and the reigning monarch.

36:00And I can understand their reticence, because though it would answer a question, does it look like these are the princes or not, it doesn't tell you who killed them. And does that then set a precedent for people wanting to open up other sets of remains? And how is that decided? So while I think it would be an amazing project to do, and you would, of course, document it, and you would do it, I think, in a much calmer way for this thing. So I can well imagine that you would just do it, you know, yes, it would be documented,

36:32but not in the same way, I think. And just a very calm and holistic study to see whether or not these are the remains of the boys. But it does ask other questions of what happens if they're not? Are they reinterred there? There's a number of questions that would need to be answered. And I think a number of kind of quite strict things that would need to be in place before I would want to be involved in something like that. And finally, Tiri, if listeners take one thing away today, what would you most like it to be? So I think, I hope they really kind of get excited about the power of DNA and what it

37:05can do, because I just think it is so incredible. So the last 30 years since I've been in the field where, you know, when it first started out, it was be, you know, I'd be there late at night and I'd be working in the lab and it's just like, I'd have the radio on and the machines are humming next to me type thing. And the paper gets published and barely anybody reads it. Now it's everywhere. And, you know, people can take DNA tests. We hear about DNA all of the time. And it's about, you know, really how powerful it is, but also really about the limitations.

37:38And we need to be thinking about how we want to use some of the new technologies that are coming forward. And I think that's quite an important thing. Professor Tiri King, thanks so much for your time. Thank you.

37:49That was Professor Tiri King, Director of the Milner Centre for Evolution at the University of Bath. And you can learn more about the case studies featured in this episode in Tiri's new book, The Secrets of Our DNA, which is out now.