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- [01:21]
Mia Sorrenti
Seehomedepot.com Pricematch for details welcome to Intelligence Squared, where great minds meet. I'm producer Mia Sorrenti. Genetics informs every aspect of our lives, from solving ancient historical mysteries to uncovering the secrets of our own identity. DNA shapes our daily interactions with the world, defining who we are and where we come from. In this episode, Professor Turi King, director of the Milner center for Evolution at the University of bath, speaks to Dr. Ganesh Taylor about her book, the Secrets of Our DNA. Together, they explore the genetic investigation identifying Richard III and how the fate of the Romanovs was discovered. Eugenics and what the code of life can and can't tell us about who we are. Let's join our host, Dr. Ganesh Taylor, now with more.
- [02:08]
Dr. Ganesh Taylor
Welcome to intelligence squared. I'm Dr. Ganesh Taylor, a group leader at the center for Reproductive Health in the University of Edinburgh. Our guest today is Professor Cherry King, who is director of the Milner center for Evolution at the University of Bath. She's well known for her academic work leading the genetic investigation identifying Richard iii and was also advising on the case of Mary Jane Kelly, the last victim of Jack the Ripper, and even more excitingly and contentiously, potentially recently led on the project sequencing Hitler's genome. Many of you will recognize her as a co presenter of the BBC DNA Family Secrets with Stacey Dooley, and has appeared on many programs, including those such as Radio 4's the Life Scientific. We're here today because she's also the author of a new book, Exhibit A, the Secrets of Our DNA, which takes us through some fascinating true stories, from mistaken dinosaur DNA to Dolly the Sheep, showing how DNA has solved mysteries and shapes our world today. So welcome to Intelligence Squared, Thierry.
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Professor Turi King
Thank you for having me.
- [03:18]
Dr. Ganesh Taylor
The first question I always like to ask authors, basically, is, you know, you've done many things in your life. You've in fact, written other books. So, you know, why. Why now? Why this book? Why now?
- [03:30]
Professor Turi King
So I actually got approached to write a book, and I'm in a. In a field that is of real interest to the general public. So, for example, I do sort of, you know, ancient DNA and forensics and genetic genealogy. So for, gosh, about two and a half decades, I have had people writing to me with questions about, you know, am I related to which of the third. That's probably my biggest one that I get, but all sorts of questions. And I've just basically found when I've been explaining genetics to people, they understand it better. It's always much easier if you wrap it in a story. So it's kind of come from that, really. I'm just sort of telling stories where DNA has been a big part of the picture and helping to, say, solve a mystery or help an individual, that kind of thing.
- [04:16]
Dr. Ganesh Taylor
Yeah, that's amazing. I mean, it really strikes me as being a very timely book, in my opinion. Of course, I've got skin in the game, being a biologist and person who uses DNA in my work all the time as well.
- [04:28]
Professor Turi King
Yeah.
- [04:29]
Dr. Ganesh Taylor
But, you know, I think that what I found really fantastic about the book is the sort of breadth of biology that you actually cover under the guise of these really fantastic stories and examples that you use to highlight the different facets. So, I mean, I thought it would be fun to start at the. At the. At the start, as it were. So, obviously, everyone has heard about DNA and this idea of, like, DNA fingerprinting. But what maybe our listeners don't know is that you actually were in the lab of the guy who discovered DNA fingerprinting, one Alec Jeffreys. And so I wondered if you could tell us first up, you know, just very basically, what is DNA fingerprinting? How did Alec come about that, and then, you know, if you can share a little bit about what it's like to meet and know somebody and work with somebody who, you know, completely changed the world, that would be amazing.
- [05:28]
Professor Turi King
Yeah. So he. He was the reason that I went to the University of Leicester, because I was actually at Cambridge during orcanet at the time, and went up there because I realized I wanted to apply genetics to questions in history and archeology. And I didn't actually work in his lab, but he was on my PhD panel when I was doing it. And essentially what he did, it's really hard to overstate the kind of the impact of what he did. It was this thing of where you could now finally identify an individual based just on their DNA alone. So none of this, like, you need photos or fingerprints or finger marks, as it's known in the tradition, how people used to do a lot of the identification, and it's still used, obviously, but this ability to be able to not even have the individual there and you can identify them using their DNA. And the way he did that was he was actually really interested in medical genetics. So he was trying to trace, you know, what are particular genetic variants that are associated with disease. And he was. So he's looking for genetic variation between individuals. And what he stumbled across was where you get, like, a stutter in the DNA. It's like a word that's repeated a number of times. And what he found was that the number of times that that word was repeated really varied between individual. And because we inherit half of our DNA from each of our parents, you get two copies of that stutter. And the more he looked in the human genome was he realized actually there's lots of these stutters. And if you use those in combination, you can identify an individual using that. And one of the first cases that was used for. Now, a lot of people don't know this because first people think about DNA profiling, they think cop shows. And instantly you can identify somebody, usually, like on the television shows, it's sort of like within half an hour, you know who it is. But his was actually an immigration case. And it's a really lovely story. So it's a woman called Christiana. She was a nurse. She's working here. She's got three of her children here. One of her children, Andrew, is back in Ghana with her estranged husband. Comes back into this country, and the home office doesn't believe it's actually her son. And the legal team have been working for two years trying to really prove to the home office yes, it is her son. And the lady working on the case, Shona York, apparently she remembers this thing. So this was the lovely thing I get to chat to these people. And she's taking the bus to work one day and she looks down on the front page of the Guardian and it's talking about how there's this new invention about how you can identify an individual and who they're related to based on their DNA. So she rings up Alec and she's really worried he won't take it on, but he takes it on. And the long and the short of the story is that he is able to take Andrew's DNA, that of his three siblings and his mother. So even without the father being there, it's like piecing this jigsaw puzzle and he's able to prove that Andrew is Christiana's son. And when you talk to the family, they talk about how years of kind of worry and anxiety is Andrew going to be sent home? It all just wiped away in that one minute. And Alec to this day will tell you, after everything that's happened with DNA fingerprinting, or profiling, as it's known now, that's still the case that he feels most proud of. And I think that's a really lovely story and it's a way of introducing people to kind of the power of what DNA can do.
- [08:54]
Dr. Ganesh Taylor
Absolutely. I mean, you really couldn't make that kind of story up. It's just an amazing, amazing combination of things coming together. But also, I think it touches on something that I found at least central to your book, which is, on one hand, there's this. There's the science of it, right? There's the, like, what does it actually do? How does it work? And then on the other side is. Is actually the human impact and the curiosity and the stress and. And, you know, the very human element of wanting to know, wanting to have certainty. And so actually, I. Maybe this would be a great time to. To talk about one of the sort of later chapters, actually, in your book, where you talk about how DNA is. Is not this silver bullet. And I think that that was something that I really took away from reading your book, because, of course, people think that, you know, it's in your DNA, it's this final thing. It's this absolute, you know, verdict, case closed, job done kind of situation. And, you know, you gave some really interesting examples about, you know, of course, on one hand, yes, the biology is what it is, and DNA is, of course, very important, but it doesn't just function in isolation. Somehow. So let's start with this sort of DNA is not a silver bullet chapter. And I'd love to have you tell us a bit more about this Phantom of Heilbon, if that's how that's pronounced. This one blew my mind.
- [10:29]
Professor Turi King
So I have a colleague who worked on this case, and the thinking for this chapter came out of a couple of things. So one was the Richard III case, where people were, you know. So I do the Richard III case, and it's about identifying his. And for me, as a geneticist, I am the first person to tell you, yes, the DNA is important, but you put it along all of the strands of evidence. It is not the final thingy. And the other thing was, is that I would get people say, you know, can you tell me if I'm related to Richard iii? DNA can tell me this, right? And I would have to say, no, it can't, actually, because of the way of our DNA is inherited. Or they would say, can my DNA tell me whether or not I am a Viking? And I thought that was really interesting use of present tense. And there's so many things that people kind of mistakenly believe that DNA can do, but you have to take it in context of everything. So the Phantom of Heilbronn case is a really interesting one. And when I first heard of it, I was like, oh, my goodness. So essentially, this is where you are starting to get a whole bunch of kind of crimes. And they're really. Some of them are murders. I mean, the first one that they kind of really spot is a lady who is, you know, she's living on her own and she's strangled. There's a coffee cup on the table in her kitchen, and they do a DNA swab and they're like, oh, my goodness. This is really unusual. It's both a man and a woman's DNA is here. Women are less likely to commit violent crimes, et cetera. And then slowly they keep finding all the way across Europe, it can be really banal crimes, like somebody has burgled a shed in a back garden, or they've been burgling a business, and then they find it on a syringe and things like this, where there's heroin. So it's lots and lots of really disparate sorts of crimes. And whenever they talk to the suspects in the case, you know, there's a woman involved here. And they go, no, we haven't had a woman, a female accomplice with us. And so the police are going, oh, my goodness. This woman is like a Criminal mastermind. She is committing all of these crimes all the way across Europe. Who on earth is this person? And she really must be quite powerful, because the people that she's working with will deny all knowledge of her and eventually what it transpires. So she becomes known as the Phantom of Heilbronn because there's two police in a car and someone comes up to the car and they're both shot and one, sadly, dies. One, you know, eventually comes around, can't remember anything, but the DNA that's in there is, again, it's this woman's DNA, and this is in Heilbronn, and this is where the name comes from. And eventually what they work out is it's not a woman who's committing these crimes, it's a woman who works in the factory where the swabs are made, where they go. So the police have inadvertently been causing this DNA sample to be found across all of these crimes because of the swabs that they're using. It's in a factory, and it was actually an older lady who worked in the factory, and it was her DNA that was being picked up at all of these crime scenes because she'd been involved in making the swabs. And this is where it is so, so important. Obviously, where the DNA being taken in context is really important. The penny starts to drop. Oh, that's why nobody's ever seen her. Because actually, if they had looked at where the swaths were coming from, it's all coming from this one location. So, yeah, so it's about how you have to take DNA in context is really important.
- [14:11]
Dr. Ganesh Taylor
It's. I mean, such a fascinating example of it, but importantly, it highlights this really central point. Right, which is that DNA is really important about the context. I mean, we would be remiss to not talk about Richard iii. And so perhaps we can talk about how did you contextualize the findings in that situation, that particular case? What was that about?
- [14:36]
Professor Turi King
Yeah. So, okay, so I got brought onto the case way back in June 2011, and the idea was that I would be involved in advising how to excavate in what's known as clean conditions, which I always find a little bit amusing, because obviously, when you're excavating, it's quite muddy a lot of the time. But the clean conditions bit is ancient. In ancient remains, whilst we're alive, we have these nice long strands of DNA and things come along and break those strands, and your body has mechanisms for fixing those, but after death, that's not happening. So if we're excavating and we touch these remains with our hands or we breathe on them. We're putting huge amounts of our very plentiful and intact DNA on these remains. And it will swamp out the signal of any ancient DNA, which at this point is going to be very, very fragmented and damaged. And so that was the whole sort of clean conditions bit. And then it's like a historical missing person's case. So if you or I went missing, they would go, well, we're looking for a woman who's about this height and this hair color and this eye color and what you were last seen in, that sort of thing. So we have to do the same thing with Richard. So we know that he's killed in battle in 1485. He's age 32. When he dies, he will possibly have battle injuries on him. We know where he's supposed to be buried. There's historical documents that talk about how he's buried in Choir, the Church of the Greyfriars. And we know that also there's a couple of contemporary historical documents which talk about him. Well, one talks about him having one shoulder higher than the other, so potentially a spinal abnormality. And then, of course, you've got Shakespeare, who's writing in the Tudor period, who goes absolutely to town on him. And they talk about him being a hunchback or bunchback toad. So obviously not terminology we use these days. And they give him a limp and a withered arm. And it's at a time when the feeling is that what you look like on the outside is a reflection of what you're like as a person on the inside. And because Richard iii, he's been killed at the Battle of Bosworth, his is the end of the Plantagenet dynasty. The Tudors come in, they are never going to say, Richard was lovely and we killed him. They're going to paint him as this figure particularly. So when we start the excavation, we actually find it's a chap called Matthew Morris, who was our site director. And he spots a little bit of Laichbone. It's the 25th of August, 2012. So it's 527 years to the day when Richard is supposed to have been buried there. And so he hops into the trench and he wants to make sure, you know, is this an articulated skeleton? And he goes, yes, it is, but we can't excavate it right then, because you have to get a license to lift human remains and you have to make decisions about which ones you're gonna go for. We've got money to do that. So we go back, we realize that actually this, this individual is in the choir. So that's number one. We know where Richard is supposed to be. We're finding a skeleton in the choir, the church of the Greyfriars. Jo Appleby does the excavation and she finds a youngish male, battle injuries, severe scoliosis of the spine. So it's all those identifying features that you're doing. And then I do the genetic analysis. So I am comparing the DNA from the skeleton with that of known relatives. So I look at mitochondrial DNA, which is inherited through the female line. We've got female lines, relatives. I also do male line relatives. So the Y chromosome, which is inherited down through the male line. Richard had no known living descendants. And because how our DNA is inherited, I couldn't just use any relatives, I've got to use those ones. And I'm getting a DNA match on the mitochondrial DNA, not on the male line. Not surprising to me because I know that genealogically it may look like these people are relatives, but if there's been a false paternity where the biological father's not the recorded father, I wouldn't get a DNA match. So I knew this. But when we're doing. Is this actually him? You've got to go, we're in the right place. We have got a youngish male, we've got battle injuries, we've got severe scoliosis of the spine, we've got this genetic matches, and you have a probability attached to all of those, which you then multiply together and that gives you a likelihood as to whether or not this is Richard or somebody else who looks an awful lot like Richard. But it's. But it's not Richard. And that likelihood ratio was 6.7 million to 1. So that translates to 99.999 to 9. 9.99999%. But what's really important there was that it's not the DNA in isolation. You bring it with all of the strands of evidence, just as you would do in any missing person's case. So that was kind of the thing behind. I think I need to write about why DNA is not the silver bullet. It's not the only thing that you use in particular cases.
- [19:20]
Dr. Ganesh Taylor
Yeah, I mean, yeah, fantastic. I also have to say that, of course, you mentioned a few things there. Like, I have to clarify, this is an articulated remain, just a complete skeleton. Is that what.
- [19:34]
Professor Turi King
Yeah, well, not necessarily complete, but it's not just a random bit of bone. So this is the Thing when Matthew, when he's watching the excavator go in, there's a bit of bone and he's going, now is that just a random bit of bone on its own or is it actually attached to something? And it was attached to a skeleton. So that's what the articulated bit means. So, yes, good to clarify that one.
- [19:54]
Dr. Ganesh Taylor
I mean, it means that even in that context, that has to be contextualized also. Right. Like, it's not just a bone fragment, it's a bone fragment in the context of a skeleton. That's amazing. Okay, so the other thing that I'm going to pick out of this is the way that, of course, you know, you just acknowledge that paternity might not be quite. There's maternity and paternity, and it might not be quite what was recorded. And there are so many stories in this book where that comes out. I have to say, this felt a little bit like at times, you know, watching a soap opera, but like historic style, you know. Yeah. There was so many stories where you're like, oh, my goodness. And then it turns out that was not rather. Right. So, I mean, let's, for a split second, let's just talk about the science and then we can. We can go into it. So you already flagged that every individual comes from a biological mother and a biological father. And importantly, because we have sex chromosomes in humans, in the type of mammals that we are, we get different pieces of DNA from our respective parents. Right. So why don't you tell us a little bit more about the sort of importance of the Y chromosome in that context, how that has transferred and the X as well.
- [21:12]
Professor Turi King
Yeah. So, okay, so this comes from my PhD and my master's project. So I started working on the Y chromosome, which just comes down through the male line and it's passed down, unlike the rest of our DNA, which undergoes a shuffling process as it's passed down through the generations. The two pieces of DNA, so mitochondrial DNA and the Y chromosome, they come down through the generations in a really simple way. So they are passed down. They do accumulate mutations as they're passed down. And that's quite handy for looking at relatedness between males. And when I was doing my PhD, my PhD was on the link between surnames and the Y chromosome. So surnames in this country, I loved this project. So we know that hereditary surnames were not really something that were around until the Normans got here in 1066. They'd already been using them for a couple of generations. Prior to that, people would have surnames or they're called by names because they could change in your lifetime. And they weren't hereditary. You didn't pass them down to your kids. But now we live in a society where generally, though, it's changing surnames are passed down through the male line. So the question for my PhD was, okay, so do all men who have the same surname, are they all related to one another? And David Attenborough ended up being my poster by you. So he's turning 100 in a couple of weeks and he was amazing. So he took part in my project. And what I was doing was I was looking at men with the stony name Attenborough, like his spelling, but also a different spelling, so B O, R, R, O, W. And just randomly around the country, I would take people with a particular surname and then I would look to see, you know, are there Y chromosomes the same, identical or nearly identical? Does it look like they're related to another? And if you look at the Attenboroughs, about 90% of them have identical or near identical Y chromosome Tomes. It's very cool. So it means that you can go, okay, so these guys are probably all descended. Well, they will be. They'll be descended from original Mr. Attenborough who lived probably, we think, about four or five hundred years ago, probably quite close to the village of Attenborough, which is just south of Nottingham. And so it was this really kind of. It was this introduction to genetic genealogy at the time, which I didn't kind of know would become so big, but it became absolutely, absolutely enormous now. But I would occasionally have people saying, well, I've got this particular surname, I think I'm related to that family over there, but we can't join. And so I would be able to look at their DNA and go, okay, so yes, it does look like you're related, or it doesn't look like you're related. But one of the things that I did make sure of, that we did during the project was not to test men who were closely related, because it could be they don't share the same Y chromosome type because they don't have the same father. So on paper, on the genealogy, they could think, you know, I'm father, son, or I'm two brothers. And you test their Y chromosomes and go, actually, you're not, because there's been a different father in there. So when I was going into the Richard III project, I knew that this was a possibility. We know it happens about 1 to 2% per generation. I find in my line of work, I Mean now sort of moving into genetic genealogy more broadly, beyond the Y chromosome, is that it's very common for people to take a DNA test and find out that their biological parent, who they usually the father isn't who they thought it was. That turns up a lot. And I warn people when they're taking DNA tests that just be aware that this is something that could turn up. And it does turn up from time to time. Gosh.
- [24:46]
Dr. Ganesh Taylor
So fascinating. Also, as a person who's very much personally, professionally interested in the contributions of biological mothers and fathers, it's a really cool use, like real world use of sort of just a, you know, a basic fundamental of our biology, basically, this idea. I didn't realize how much mitochondrial DNA is relied upon actually in, in forensic. That was, that was a new one for me. The fact that you get all your mitochondria from the egg from which you came from, from your mother can be leveraged in this context to sort of answer questions. Yeah.
- [25:28]
Professor Turi King
And the Romanov case, I think, is probably one of the most famous ones of that one. And that was the whole reason I was sitting in a lecture theater in Cambridge doing biological anthropology. And a lady called Erika Hagelberg was our lecturer and she worked on some of the really early cases. And it was the Romanoff case. And that was the thing that changed the direction that I went in. Because this is Tsar Nicholas and his wife, Tsarina, their five children, some of their household, they're killed in the Bolshevik Revolution and their remains are hidden in a, we now know, in a forest. And for decades they weren't found and people didn't know where they were. And then in the early 90s, the remains are found and examined and again, it's using DNA alongside other evidence. So, you know, they do the osteology, they look at the bones. Does this look like they're people of the right age? They clearly had injuries, violent, violently caused injuries. And all of this fit with what, what they knew about it. But what they did was they did the standard DNA fingerprinting to look to see if this was a family group. And then they kind of go, okay, so this does look like it's a family and we've got people who are unrelated, but is it actually them? And Prince Philip is a female line relative of the Tsarina. So he, they're both descended through Queen Victoria. So what happened was he very kindly gave his DNA at the time and they were able to use his mitochondrial DNA and match that to Tsarina and to the children. And then they were able to do further analysis to identify the Tsar. And again, it's one of these. Another mystery came out of it because there was a woman called Anna Anderson who lived in the US who claimed to be Anastasia, one of the daughters. And it's this incredibly kind of romantic story about how she's managed to survive, she's managed to get to the US and she's, I'm Anastasia. And even though members of the family who had known, you know, the Tsarina and the children had said, no, that she's not, she maintained this until the end of her life. And when the remains were first found, they didn't find the remains of two of the children, one of whom could have been Anastasia. So there was this question over this. But since then, obviously, the DNA analysis was found. Yes, no, we have found all of the children, and no, she wasn't Anastasia. But of course, I love this ability of genetics to be part of the key to solving some of these mysteries. It's amazing. I mean, of course, I love that kind of thing.
- [27:52]
Dr. Ganesh Taylor
I mean, I was gonna say I'm also totally biased in this context also particularly of the fact that Anastasia came out, because I am of that generation that was raised on the films that romanticize this idea of princess who escapes. And I think there's a lot of stories that humans, I mean, tell about themselves, about their past. There's this real value that we place on, you know, stories not just from our deep past, but exactly, as you say, sort of from our immediate history. And so we have this sort of fascination with that and knowing, and DNA has this really important role to play in that, but also can, obviously, as, as mentioned already, can sometimes throw us.
- [28:39]
Professor Turi King
That's right. And I think you're. I think you're completely right. I think it's. A lot of it is about identity. So certainly when doing DNA Family Secrets with Stacy Dooley, when people come to us, oh, my goodness, you can really, really feel the longing. There's a question in their lives that DNA could help answer, and it's either if they're adopted and they don't know what their ancestry is, or they don't know who a particular parent is, or they've taken a DNA test and they've realized that their biological father's not who they thought it was or maybe or they've never known. And you get people who are donor conceived and they would just like to know, what's my ancestry or do I have any donor siblings? And when they hired me, they. They were like, you're going to be the really serious scientist. And Stacy is going to be touchy feely. And I joke because I mean, I, I, I will cry at adverts. It's like, you know, and so you put somebody in front of me who is, there's a longing, a real longing that comes off of them. And I'm this massive empath, so I can really feel it and just how much it means to them to be able to answer that question. And so there have been many a time where I'm able to give them the results and they're in tears and I'm in tears. And you can hear the camera person by me going. Because it is just so incredibly moving. And I think the power of DNA to do that is just absolutely incredible. I mean, I think one of the things about the program that we do, which is we show the reality of that DNA testing. So sometimes there are times where we can't answer your question. There are not the DNA matches on there at the moment for us to be able to answer that question. And there have been and it's about that, you know, it could be in six months, it could be in a year, it could be two year that we can answer this question. Other times you can answer the question within minutes because the DNA match is on there or their DNA match is such that you can build the family trees and do that. And I think that that's also quite important to show is that sometimes you can't answer the question. And there have been cases where the show goes out, somebody calls in and says, ooh, that looks just like someone I know or one of my relatives. Would you take a DNA test and you can answer that question for somebody. So I think it's about the reality about what, you know, genetics can help you, but there's other factors that come into play sometimes.
- [31:07]
Dr. Ganesh Taylor
Yeah, absolutely. Let's actually talk about the sort of DNA databases that you're talking about where you have to look for matches. Because I think that people don't realize that if you have done sort of DNA testing, I'm not sure if we're allowed to discuss brand names, but 23andMe was the big company that really made it, for example, a few years ago. Yeah, but yeah, I mean this idea that you would get like updated results was not something that I think were static. How does that work exactly? Why is it static?
- [31:49]
Professor Turi King
So when you take a DNA test with one of these DNA testing companies and there's a number of them out there, is that they take your DNA and you go on the Database. I mean, you click to say, yes, I'm happy to be involved in DNA matching. And you opt into these various sort of aspects of it. And in the early days they would have, for example, reference samples and it's taking your DNA and it does the DNA typing and it's not doing the same DNA typing as for DNA profiling, which is looking at those tiny little stutters and just a few of them. This is looking at hundreds of thousands of these little tiny genetic typos. It's almost like they're single letter differences that we get between our various genomes. They look at hundreds of thousands of them and then what they do is they go, okay, so you've got this particular genetic makeup. They don't even do it for your entire chromosome. They'll take your, when I would say chromosome one, they'll kind of use the computer to chop it up into little chunks and they go, right, where's this chunk from? And it will look in this database going, well, who has this matching kind of chunk? Oh, it's somebody who lives in, I don't know, Eastern Europe, for example. Where does this chunk come from? Oh, it comes from the Caribbean, for example. And it will do that with all of your DNA and it will do it a number of times. So when you get, get the results back, what you're getting is, so you're getting about 45% this, but it'll be somewhere in between that. It's not like you are 45%. Whatever it will be, this is 45%. This is where we're getting the matches, is this sort of area. So every time the database updates, you will get a slightly different thing because it might suddenly be that actually now that little chunk of DNA doesn't match to somewhere in Eastern Europe. It's somewhere. And so you're getting these differences. And also in terms of as more people take DNA tests, in terms of your genetic matches going well, you look like you're showing this amount of DNA. This looks like it might be a third cousin type thing. Those numbers of matches are increasing all the time. So for example, I was doing a chat called Matthew for DNA Family Secrets. And I'm looking at the matches and he's coming back at the Seychelles. And then suddenly someone pops up and it looks like it could be a half sibling's child. And so it's in between, we've done the filming with Matthew. This is where you're from. You're from the Seychelles. This match pops up and it's like, oh, my goodness, who's one of your parents, is one of your parents from the Seychelles? And so it's talking to them. We found a half sibling that way for him. And oh, my goodness, when you look at Matthew and his half sibling Carl, they just. Oh, my goodness, they so look like siblings. And that was a really lovely moment. And then being able to eventually get the matches, to be able to. To find his father. So slowly things are. Every time somebody takes a DNA test, it increases the chance that you might find a match. That's helpful for you. To answer your question, I have to ask, actually.
- [34:42]
Dr. Ganesh Taylor
So how does. How does, like, political diasporas, for example, displacements of people manifest in these databases?
- [34:53]
Professor Turi King
Yeah, well, they do, yeah. So, I mean, I can be finding that. I'm getting a DNA match for somebody with an individual who is, for example. So in this country, we have people who are from northern India and Pakistan. So when you have the new borders are put in and you get these migrations of people who come over here, more and more of the people who are the result of these kind of political diasporas are taking DNA tests because they want to know a little bit more about their ancestry. So, yes, you definitely. We definitely find traces of that in these databases. And I always have to say, look, if you take a DNA test, it's not going to give you a country because DNA doesn't follow political borders. It just doesn't. And political borders change, as we know. But it will give you an indication as to areas as to where your ancestry might be from. And that might be enough to answer your question for you.
- [35:49]
Dr. Ganesh Taylor
Yeah, that's so fascinating. I mean, I. I'm personally very grateful to hear that. As a political refugee myself, it's always been something kind of interesting about these sorts of ideas of how movements can affect this sort of thing. While we're talking about it, a bit of a shift in gears here. So we've talked a lot about humans and the stories they tell each other about where they come from and all that kind of thing. But I think it would be really interesting to pick up on something that you've mentioned about genetic conditions, about health, basically. Yeah. And so one of the things that happens, for example, when you do these kinds of private tests is they can say things like, do you want to know if you are a carrier for X, Y, Z condition? And again, in the book, you talk about BRCA for. I mean, you talk about a number of them, but one of the ones you highlight is the BRCA gene, for example. And so I wondered if you could tell us a little bit about sort of how, how certain can people be based on a genetic test for a genetic condition? Yeah.
- [36:59]
Professor Turi King
So I am the first person to tell you to with the genetic testing that's done through some of the genetic testing companies like 23me and Ancestry and things like this. Be careful with those. It's the sort of thing where they don't, they're not the experts in this is a particular condition. And so therefore we are looking at all of the genetic variants that are involved in that particular, particular condition. They use some of the genetic variants. So for example, I understood that one of the testing companies will tell you whether or not you are particularly sensitive to caffeine based on one genetic variant, but they don't look at another genetic variant which interacts with the first genetic variant to change how sensitive you are to caffeine, for example. And this is where I hope I kind of really explain is that genetics is very, very complicated. There are some cond where it is very straightforward in terms of whether or not you're going to develop a particular condition because you have a particular genetic variant. And hunting disease, there's the same kind of, we talk about the same kind of conditions a lot of the time because they have their people know about them and they're very well. So like cystic fibrosis, Huntington's disease ones where they have a very simple pattern of a genetic inheritance where if you have a particular variant you will go on to develop this particular condition. Huntington's is a very common one that we chat about. Cystic fibrosis is another one where if you've got two genetic, sorry, genetic variant each from one parent, so you can have a parent who has the genetic variant but because you've got two chromosomes, you've got the genetic variant on one, the completely kind of normal genetic variant on the other, if that's the way you want to call it. There will be a carrier, but they won't have the condition. But if they happen to have a child with someone who's also a carrier, there's a 25% chance that both mom and dad will pass down this particular genetic variant, which would mean that the child would go on to develop cystic fibrosis. And those are quite simple disorders. And then you get into ones where actually it's far more complex. And I go on it into. So I talked about a little bit about Angelina Jolie who I think was very brave and did an op ed piece in the New York Times about how she knew that there was breast and ovarian cancer in her family. And she went and got, got tested genetically. And because we know a lot about how BRCA1, the gene works and people's risk factors that they can give her a probability of going on to develop breast cancer or ovarian cancer. And she very publicly talked about how, you know, that was a really difficult decision and went through a preventative mastectomy in order to make that less likely that she will develop it. But then there's. And with BRCA1, we already know there's interactions with environment. And this is where so many conditions come in. So you have conditions that are monogenic. A single gene is involved, but most conditions are polygenic. So this will be hundreds of genetic variants across your genome that each individually both predispose you or protect you against a particular condition. And on top of that, you have this huge layer of the environment. And that can be everything from what you are eating to are you getting exercise, are you smoking, have you got trauma that happens to you in your lifetime. All of these things will have an impact on your genetic predisposition. But whether or not you'll actually go on to develop this. And that's something that really came up in the Hitler project, which was a really. And something that we have to be really, incredibly be careful when we talk about, because he was interesting in that he had a genetic variant that is known to be really sort of known to be involved in a genetic predisposition towards underdevelopment of genitalia. And that one's quite well understood, and that's a quite straightforward one to do. But we had a team, the ISAC team in Denmark, looking at genetic predisposition towards neurodevelopmental orders and psychiatric disorders. And they were looking at something. So this is a polygenic score is what they're doing. So this is where scientists will take a lot of people with a particular condition and they will look at the genetic variants that they seem to have more frequently versus people who don't have the condition and they don't have these genetics or they do, but it's not as much of a frequency. And so what you get is this, like this. It's a bell curve where you go, okay, these people with this condition seem to have a lot of these genetic variants. These people at this end don't. And you can take an individual and you can place them. Where do they fit on that bell curve? And it's not diagnostic. It's a genetic predisposition. And Hitler was very unusual because he came in the top 1% for schizophrenia, bipolar and autism. And there's a number of kind of massive caveats in here. This is a genetic predisposition. The team actually did a calculation as to what would be the probability of Hitler being diagnosed with one of these things in his lifetime. And that comes up. And at 5%, so 95% chance that he wouldn't have been diagnosed with one of these conditions, this is really not to. What we were very concerned about is like, oh, my goodness. So he had these particular conditions. No, we don't know that. Second of all, oh, well, that explains it. And obviously people with these conditions do not go on to commit the sorts of crimes that he did. In fact, they're more likely to be on the receiving end of them. And I think that's another really important thing. And obviously Hitler did not act on his own. He had a lot of people, hundreds of thousands of people who all helped him in his thing. So it's very much a case of we have to be really, really careful with what we can say from somebody's DNA. And that was something that I've really been at pains to try and get across with that.
- [43:04]
Dr. Ganesh Taylor
I really appreciate you flagging all of this because it is the perfect example, I think, most of. Of both the power of genetics, but also the limitation of genetics to actually tell us what is valuable, what do we value, and actually certainty of what comes out. Now, as we sort of reach the end of our conversation and we kind of zoom out, Hitler's the perfect person basically from which to. To. To zoom back out from. Because of course, you know, aside from causing wars, Hitler had a big role in the eugenics movement. Eugenics is premised on the idea that DNA and your genes are inherited and they are inheritable, and that therefore they can be deliberately arranged and organized, much like selective breeding of animals. And you talk in the book about the fact that of course, there are two different types of broad methodology that are employed, which Hitler government also employed. One called positive eugenics, where they encourage people of certain types to breed, to try and concentrate genes that they're interested in, and one called negative genetics, where they committed what we now fully understand and accept and verbalize to being completely unacceptable atrocities of humans against humans, sterilization, killing people off to prevent reproduction, and a sort of acquisition of these kinds of genes. And I think. I think it's really important that especially in. In the context of the book that you've written, it becomes really apparent, I think, that of course DNA is instructive but it is not always the be all and end all. And in particular in the kinds of conditions and traits that he was concerned with. It is not a. It is, for example, for Huntington's disease or cystic fibrosis. Right?
- [45:10]
Professor Turi King
Yeah. And I think you're right. And it's a real warning, I think, because the irony I found in this whole thing is that Hitler has to sign this thing to marry Eva Brown and that I am free of hereditary disease. And yet he did have hereditary disease. He's not a genetic. He wasn't a geneticist. Us looking at the DNA would go, yeah, but that only tells us a little bit about this. But he probably would have looked at it and thought, oh, my goodness, he probably would have sent himself to the gas chambers. And I think that that's a really interesting kind of thought because it's this lack of understanding of DNA. If you don't have that deep understanding about what DNA can and cannot tell you, and I'm hoping that's kind of what comes out of the book, that people understand that. It's not. It's very complex. It's a very, very complex thing. And it's an area that we have to be so careful about because it's very hard to have positive. Having positive eugenics is negative. Eugenics is on the other side of that and they're interlinked with one another. And to have positive means that you're suggesting that something is undesirable. And I think that that is a very, very slippery slope that we get into. And I think it's something that we. I hope people become more educated about.
- [46:30]
Dr. Ganesh Taylor
About.
- [46:30]
Professor Turi King
Yeah.
- [46:31]
Dr. Ganesh Taylor
I'm no psychologist, but I think that. I think that there is something that we all have about this idea of our bodies and what our bodies. That our bodies are somehow final in a. In a value in society. And we kind of over attribute our human values to our actual bodies. And then when you have those kinds of thoughts in the context where we know about genetics and genetic inheritance, it becomes really hard to be able to hold multiple concepts in your mind. Really.
- [47:11]
Professor Turi King
Right. Yeah. And that DNA is not deterministic. I think that's such an important thing. So when somebody says, it's in my DNA, of course, as a geneticist, I'm like, it's definitely not. I mean, unless it's something really serious, but.
- [47:26]
Dr. Ganesh Taylor
Exactly. So this is. This is part of it. The complication, I think at the absolute heart of how people think or don't think about DNA is that there are some parts of your genome that are deterministic. But actually it's far more not deterministic, far more complicated, far more based on your environment and everything else that happens, happens to in your life. But I think, because human beings, I personally think, and this is not a professional opinion now, but I get this sense that because we as humans like to have our certainty, we latch on to those few things that we can say with certainty and then we extrapolate that out to everything. And then you can do things like, you know, using these DNA tests, a bit like, A bit like astrology. I mean, oh, I can't now the fact drink this much coffee because it's in my DNA, this sort of fatalism thing.
- [48:26]
Professor Turi King
So I hope that's something that really comes out of the book that exactly what you're saying. And. I just think it's so important for people to understand more about genetics because we are now able to do so much in terms of genetic engineering. So I think epigenetics is incredibly interesting, but also genetic engineering and the fact that we now have crispr, I mean, it's an incredible technology. So Jennifer Doudna talks about we can change evolution. That's pretty extraordinary. We need to be having a discussion as a society about how we want to use this technology. I mean, it's a joke about. So he Jiankui, he is genetically engineering embryos which then go on to be babies. Don't throw the babies out with the bathwater. This is a kind of, of a really amazing. We shouldn't be saying no, we can never do anything like this, but there has to be guidelines and guardrails and how do we want to use this and where are our boundaries as a society? And that involves everyone talking about this sort of thing. And we need kind of legal representation, we need bioethicists involved and the general public to how do we want to move forward in the most humane way with the technologies that we have now?
- [49:44]
Dr. Ganesh Taylor
Absolutely. And you know, if I say so myself, I think actually a book like your new upcoming book is a really, really important building block in that process because actually increasing the literacy of everybody and around DNA, genetics and making people more aware and comfortable with the sort of duality of, of which parts of your DNA can be deter versus not is really, really critical and is a really critical foundation stone to having those kinds of conversations, basically. So with that, Chiri, thank you so much.
- [50:28]
Professor Turi King
Thank you for such a lovely chat.
- [50:30]
Dr. Ganesh Taylor
That was Professor Turi King, author of the Secrets of Our DNA How Genetics has Changed the World, which is available now online and in Stores. I'm Dr. Ganesh Taylor. You've been listening to Intelligence Squared. Thank you for joining us.
- [50:46]
Mia Sorrenti
Thanks for listening to Intelligence Squared. This episode was produced by Ginny Hooker and it was edited by Mark Roberts. For ad free episodes and full length recordings, you can become a member at intelligencesquared.com forward/membership. If you'd like to join us at future live events, you can find our full program and buy tickets over@intelligencequote squared.com attend. You've been listening to Intelligence Squared. Thanks for joining us.