Unchained

Music

Sarah Fourcheraud (producer)

Welcome to Decoding Nature’s Alphabet

Prof. Turi King

What we really need is a kind of a binding, uh, international consensus on what kind of research can go on and how that should go on, but it needs to be able to police it. So, it needs to be something that’s a worldwide thing that, that actually comes into law.

Ron McCullagh (presenter)

If you’ve already listened to episode 1 of this series you’ll have heard how DNA science is already changing lives. In this episode Professor of Public Engagement and Genetics at the University of Leicester, we’ll be discussing the morality and ethics of editing genes.Hello again Turi

Prof. Turi King

Hello

Ron McCullagh

In episode two we discussed Crispr. So, tell us more about “Clustered Regularly Interspaced Short Palindromic Repeats” please?

Prof. Turi King    

Okay. So the work on CRISPR Cas 9 headed up by Jennifer Doudna and Emmanuelle Charpentier  led to them winning the Nobel prize for this in 2020, the Nobel prize for chemistry. Basically, what they, and others, had found was that when bacteria are attacked by viruses, what happens is if the bacteria survive that virus, what it does is it keeps a little bit of that virus, genetic material in a special place in its own material.  It’s got a bit of a defense mechanism and that has got this little piece of genetic material from the virus that’s invaded before. And what it has is, um, a little protein called Cas 9 and what this bit of genetic material does, is it kind of flexes, you know, like a, a find and replacing, like, if you’re looking for a particular bit of text in a larger text, it’s like, I need to find this particular kind of string of words… same kind of thing. So, it takes this genetic material from the virus. It goes “Oh, I’m looking for this” and this little protein goes along with it and if it finds that bit of genetic materials in these viruses invaded, it will, the Cas 9 protein will cut it. So, it’s destroying the viral genetic material to stop it from attacking the bacteria again.

So, it’s a very, very clever little system, but what the researchers realised was that, well, that means you can actually use this as a kind of guide. RNA is called to do the same thing in other organisms. So, it’s look for this particular piece of genetic material out there somewhere and something that’s invading or, or in a bit of DNA or this kind of thing, and where you find it. I want you to cut it. And so you can actually program this to look for whatever bit of genetic sequence you particularly want. And so this has been incredibly useful because it’s things like you can look at all kinds of, of things. So, you can use it for example, within plants. So, people are looking at ways of, of can you alter genes that are involved in, um, the amount of gluten, for example, that’s in wheat?

So, could you grow wheat varieties that have got lower gluten content for people who’ve got celiac disease, for example. There’re interesting things like, could you, um, in mosquitoes, can you affect genes that, uh, have an impact on the ability of the malaria parasite to replicate within the mosquitoes? And then that gets, that gets passed on. So, can you actually make it so that mosquitoes don’t actually carry malaria or are resistant, uh, to carrying malaria and so then don’t pass it on. Some of the ways that they’ve thought about doing this might mean that actually you have entire species of mosquitoes. Uh, they they’ve been able to do this in the lab where they actually get the mosquitoes, they have more males than females, and so eventually the entire colony dies out. Now that’s got some really interesting ethical implications because if you release this into the wild, that leads to questions, like, are you going to be getting rid of entire species,?

Um, but there’s also interesting things in terms of things like gene therapy, it has got implications for people with genetic disease, such as sickle cell anemia or cystic fibrosis. Can we use the CRISPR technology to alter the genes which are causing these particular diseases to actually cure them or help people live in a, in a better way? So, there’s a number of kind of ethical things that you have to consider with this. And obviously if it’s something like it’s, it’s working to cure disease or help people with disease, I think most people would, would go along with that. But where you start to run into the issues is things like something we touched on previously in a, in another podcast, which was the issue of He Jiankui, who, who used CRISPR to alter embryos. Now this is affecting germline. So, it means that if these embryos, you know, the, they develop and they become children, which in this particular case, they did, any genetic alterations that have been introduced through something like CRISPR, which is what he was trying to do, then get passed on to their offspring as well. So not only does it affect them and they had absolutely no choice in this, but it would go on to affect any of their offspring as well. And this is where you have both the positives and the negatives of these new technologies.

Ron McCullagh

Why do the words bull and China shop jump into my heads whenever you say these things?

Prof. Turi King

It, I mean, it’s a very, very exciting technology and its uses are absolutely amazing. As I say, I mean, the, the ability to potentially cure diseases or help people with particular diseases. I don’t think people can really argue with that. Um, but it does definitely need some sort of regulation. So, and this is an interesting thing, because as say with He Jiankui what he was doing was he was looking at embryos and he was trying to, he used CRISPR to actually change embryos. Now this does happen in this country. There’s really interesting work going on by Kathy Niakan, who, um, is looking at, at spare embryos that are left over from IVF. Uh, but she’s only allowed to have them keep going and dividing first a certain number of days after which they have to be destroyed. But what she’s been doing is using CRISPR to say, knock out a particular gene, and then she wants to, so what, what does that gene do in development?

What happens when you knock that out with the idea that you can learn more about genes that are involved in development, this will help people who presumably are, uh, you know, having IVF and this kind of thing. So, I find it difficult to argue with things like that, where it’s been regulated. Um, you know, it goes through a number of ethics boards. So, she had to go through the human fertilisation and embryology authority and then through another ethics board. So, people are really, really looking at what is the research that’s, that’s being proposed. Why what’s it for, what are the benefits of this and what are the possible dangers with this? And actually, one of the papers that, that came out of that showed that sometimes with, with the CRISPR technology, you don’t necessarily just knock out the bit that you’re interested in.

You can have, what’s known as off target, uh, where it does things off target…not where you were expecting it to. And that’s been another really useful thing about this kind of research is that it, it shows that look, there’s still some pitfalls associated with it. It’s, it’s still, you know, being developed. And so I think people, I think they find it hard to argue with that one. It’s definitely where it starts to go into things where it’s germline. I mean that, yeah, I mean, I think the entire scientific community were absolutely aghast at what happened there. And it was interesting because it meant that very prominent people, such as Francis Collins, who’s the director of the National Institute of Health in the U S is, is calling for a binding, uh, international consensus on what kind of research can go on and how that should go on, but it needs to be able to police it. So, it needs to be something that’s a worldwide thing that, that actually comes into law to some extent and at the moment there is no consensus on how that could and should work.

Ron McCullagh

Now we will come to that I think in more depth as we develop this discussion, but we’re talking about the potential for genetically modified humans. And if we ignore the lines that can, and perhaps should be drawn, what’s possible. For instance, if we could feed an artificial intelligence, the complete DNA sequences of a million human beings and their associated health records, couldn’t this AI intuit new versions of human beings, certainly more healthy, but maybe with characteristics, such as non-smokers or humans with less likelihood to commit crime, where does it end? Should we even begin?

Prof. Turi King

So, this is a really interesting, um, thing that you bring up because people are already doing this. So, Genomics England, for example, uh, set out to sequence a hundred thousand genomes, and these are genomes from people and associated with their health records. So, they were particularly interested in rare diseases and cancers. And what they are doing is they’re looking at these genomes and it’s, it’s like genome wide association studies, but they’re now able to do it on, on a much larger scale. So, genome wide association studies are you when you go, okay, we’ve got these people and they’ve got this particular disease. These people don’t have that particular disease. What is it about this group of people who have the disease? What is it within their DNA that they have in common that seems to be associated with having this disease? And it allows people to go, okay, so this area seems to be involved.

It’s like putting a flag down in the genome and going “all right, there’s something going on here that seems to be involved in this, we don’t necessarily know what it is”. We can start to zoom in on it and have a look and see what’s there, as opposed to people who don’t have this particular disease with these kinds of really, really big datasets and the computational ability to kind of go through all of this. You can start to home in pretty quickly on this. And you can start to look at, at not just variants that we think are possibly common within the population that might be associated particularly but also rare variants, ones that seem to be relatively rare in the population, but that might have a relatively big impact on a particular disease. So, you’re right, it gets to the point where you can look at a, at a particular genome and have some sort of an idea  as the predisposition of somebody towards a particular disease.

Ron McCullagh

Well, I, I worry that in the future want to be, parents will have two simple questions to answer. Do you want a genetically modified child? And how much can you afford? And by the way, here’s our catalogue? do have a look.

Prof. Turi King

Yeah, see, this is, this is where we are in a really, really interesting area. I mean, there is a, a company that I saw relatively recently that is offering a service to do sequencing of potential parents. And then give them the idea, statistically, of how likely it is that their child would have one of a particular set of diseases. And presumably that’s going to be an expensive thing to do. And so only people with a, uh, a particular sort of income level would be able to do that sort of thing. I mean, you, you have to remember that it is perfectly possible for people, if they are going through, um, IVF or where they’re going, they’re having children. They know that there’s a genetic disease within the family already. You can screen embryos for that, things like that.

So, this, this does happen already, but the fact that there’s, it’s getting, um, sort of slightly commercialised starts to kind of go into an interesting area because then only certain people can access that. And at the moment whilst the, what they are looking at and giving people information about is, is about genetic predisposition, towards particular sort of diseases. Where does that stop? Where’s the line in terms of what you think it’s acceptable to look at and not acceptable to look at? I mean, I think it’s relatively straightforward if it’s something to do with disease, then I think for most people that particularly diseases that would limit somebody…an offspring’s life span, for example, or if their quality of life, uh, would be impaired. I think people are usually, um, you know, fairly like, okay, I can see how, how that would happen is when you’re starting to look at traits that have nothing to do with health, then you get into a really… obviously you’re getting into an area which, which, yeah, it, that’s very, very difficult to think about.

Ron McCullagh

And different countries, different societies, different cultures are going to have a different approach to this problem. Some will think perfectly reasonable to carry on forward and develop better examples of humans and others will, will say, no, that’s wrong. We shouldn’t, we shouldn’t be creating, um, two types of humans. Um, although we, as you say, we already are in effect, at that threshold where there are now going to be genetically modified humans, whatever we do, because we’re trying to stop diseases going forward.

Prof. Turi King

Yeah. So it’s, I suppose it’s the distinction between genetically modified and or embryos where they have selected the embryo, because it doesn’t have a particular disease, which are two separate things. And there is certainly, there’s like… The World Health Organization has got a global network of, of kind of collaborating centers for bioethics. There is certainly, um, it’s not a global oversight, but, uh, but a global push to be thinking about these particular issues, but it’s whether or not it’s something that becomes, you know, enshrined in a law, that’s the way of kind of, of making sure that certain things don’t happen. I mean, that was the big thing about the, the He Jiankui case that actually he hid things. Um, he, you know, didn’t, he wasn’t open about what he was actually doing and that’s how he was able to kind of manoeuvre past, um, particular sort of ethical considerations.

Ron McCullagh

Except that he was collaborating, it appears, with some American academics as well.

Prof. Turi King

There seems to have been researchers who knew about what was happening, some of them, you know, had, had counseled against it and thought that possibly he was no longer doing it, where it seems other people seem to know that it was going on and didn’t say something about it. And this is where you get into really, this is really, really murky areas in terms of the scientific community. Because I mean, from my experience, the vast majority of the scientific world and everybody I know, um, would be completely aghast at the idea of genetically modifying embryos which would then go on to become, you know, children, but obviously not everybody thinks that way. And, and I know that investigations are going on at the moment as to what people’s involvement or at least knowledge was of what was going on over there.

Ron McCullagh

And in a nature article in February, 2019, one of those scientists, who’s in the spotlight, an American academic, um, he gives a number of reasons why he didn’t do anything. And one of them was, he didn’t really know who to complain to, you know, he had concerns, but I mean, he’s no connection with the Chinese scientific regulatory authorities. And, and he didn’t really know it wasn’t, it didn’t seem appropriate to report it to his own authorities. So there’s no structure as it were for people to raise concerns within different parts of the scientific community about these issues.

Prof. Turi King

Yeah. I mean, that’s exactly it, different countries have got different regulations. So, many countries ban research on embryos or have got very strict, um, sort of guidelines and laws, even about how you can, you can actually look at human embryos, whereas places like the U S and China don’t have laws that specifically prevent it. So, this is why I say so Francis Collins, who’s, you know, incredibly eminent scientist has been advocating for some sort of international body. One suggestion has been the United Nations whereby, countries sign up to an agreement as to what, what people are allowed to do with research. But that’s the issue, We do not, at the present time, have an international bioethics body that is capable of coming up with consensus guidelines that are then enforceable across the world

Ron McCullagh

It seems unfair to keep pointing the spotlight at China, but there’s, there’s even stories of genetically modified humans for the Chinese army.

Prof. Turi King

Yeah. So, we don’t know whether or not this is happening in, in other countries at all, uh, as, as well for all we know. And again, it’s almost science fiction, isn’t it, it’s this idea of being able to genetically modify people, you know, presumably embryos, uh, to select for particular traits. And there’s a, there’s a few things here because presumably you would be selecting for traits such as, you know… speed and endurance, strength. Um, would you be going for ones that are psychological? So people would be less worried if they, if they kill somebody in the, in the course of what, what they’re doing. Um, but also because at the moment the genetics involved in these particular traits are still not properly understood. For most traits we know that it’s not a simple straight-forward case – its many genes combined with environment that produce these traits.  So, the ability to carry this out at the moment, while you hear that particular countries are interested in it, it’s not something that’s actually possible in terms of what we know about DNA and it’s impact on particular traits. Still, we do need to get on it in terms of a regulation around it. And it leads to really, really interesting ethical discussions around what we should and shouldn’t be looking at. And you’re, and you’re absolutely correct. It may be that certain cultures and countries have got different ideas around that. And that’s why it needs bringing together in a big consensus.

Ron McCullagh

Well, let’s move into the more practical world of romance. How do you think AI meets DNA meets dating services would work out?

Prof. Turi King

Well, I confess I haven’t watched it yet, but there is apparently a Netflix series called The One. And my understanding is the premise is that you would have your makeup, your genome sequenced. And it would look for people who you, you know, who’s the one? Who’s the one person who you pair with the best? And this is where my little geneticists… I start waving my fists around, because again, it’s like I’ve said previously, we are not a blank slate when we are born. We, know that particular traits have got a genetic component to it and, you know, personality. DNA is not everything and we have proof of that due to studies of identical twins. So studies of identical twins have been used to kind of pull out some of these things. So, we know  that certain things to do with our personality and intelligence as, as measured by IQ, et cetera, et cetera, there does seem to be a genetic component to some of that, but we also know there’s a huge environmental component to it as well.And so, this idea that you can just look at somebody’s DNA and say, well, you’re going to be best matched to this person, just makes me want to throw things at the television. I know it’s only TV, but it’s, it’s just simply not the case. We are not our DNA. DNA is not our destiny. We are, uh, uh, an absolute mixture of the two.

Ron McCullagh

Let’s move on to DNA testing because it’s likely to become more common, isn’t it? Um, for instance, I wonder, will employers be wanting your DNA analysis along with your CV?

Prof. Turi King

No matter what your DNA says you are, it’s, it’s only part of the picture. So, you can imagine though, that I think it would have to be in terms of things like health. So are you, you know, genetically predisposed towards a particularly nasty disease, this kind of thing. Um, but in terms of, but how that would come into the workplace, I mean, that starts to become discrimination, obviously. Um, how so, how it would come into the workplace again, it’s just not a straightforward link between genetics and personality and how well you might work with people, or whether or not you might be a better leader or this kind of thing. There just isn’t that straightforward link.

Ron McCullagh

But don’t, we understand that insurance companies are already wanting to get access to, uh, to, to potential insurees DNA.

Prof. Turi King

So my understanding is actually that, um, a law has been passed against that. So for example in the US The Genetic Information Nondiscrimination Act  of 2008 prohibits health insurance companies from using genetic information to make coverage or rate decisions. But it does not extend to life insurance, disability insurance or long-term care insurance. So there is no federal law that limits the use of genetic information by life insurance companies. In the UK, The Association of British Insurers andthey have a Code on Genetic Testing and Insurance that states that people who are seeking insurance will not be asked or put under any pressure to take a genetic test to obtain insurance cover.

It commits insurance companies to treat applicants fairly and not require or pressure any applicant to undertake a predictive or diagnostic genetic test. … only exception being if you are applying for life insurance over £500,000 and you have had a predictive genetic test for Huntington’s Disease. Only in this circumstance do you need to tell the insurance company the result of the test, if they ask.

Ron McCullagh

So that’s fascinating that, that there is regulation, uh, in, in this sphere, but it’s sort of early stage as it a recognition. There’s something unfair about making judgments based on people’s DNA.

Prof. Turi King

Oh, absolutely. It becomes discrimination. And at what, what is it that you’re going to look at, particularly in what things are you going to use to sort people into presumably into little boxes based on what’s in there, their DNA, what, which bits are you going to look at? Which bits are you going to prioritise? So yes, it, it, it absolutely, um, yeah, it it’s, it would be discrimination if you were going to do that.

Ron McCullagh

Well, talking of which, uh, I’ve submitted my DNA for analysis, and you have had access to the results. And I’m hoping that you’re not going to tell me anything too shocking.

Prof. Turi King

Not at all. So, it’s, I find that these tests are really, they can be quite fun to tell you something about your, your ancestry. They can be absolutely amazing if you want to be doing what’s known as genetic genealogy. So, if you want to run the genetics alongside your standard genealogical research, it can help you find distant relatives that you didn’t know that you had. So, when we are looking at your report as to what comes back as, as your ancestry, you are coming back as having matches that are overwhelmingly British and Irish, which is I’m guessing what, what you would expect, um, from what you know about your, your family history. Um, and it, it depends on whether or not, and this has got to be quite good, one of the really good things about, about the testing company that you went with is it allows you to look at kind of how stringent you want to be about those results, because what they do is they take your DNA and they actually kind of cut it up on a computer.They cut it up into little bits and they go, “okay, which bit where?” “Who in the database does this little bit match?” And it will do that a number of times for all these little bits of DNA. And it will repeat it over and over again.

So, what it’ll do is look kind of go, okay, so this is matching this particular individual or reference population. It actually might be a good match to another individual who’s from a different part of the world, but it’s most closely matching this one. So, it puts you in that kind of little box and says, okay, you’re X percent this, but they’re quite clever in the algorithms that they use and they do things that are kind of known as smoothing. So, it doesn’t just look at one, this little section of DNA and go, okay, well that bit, it looks like it comes from Finland. It’ll also look at sort of bits either side and goes, well, does that look like it also comes from Finland, it’s called a sort of smoothing process. But with many of the companies you can also change the stringency about this kind of matching process. So, when the results come back, they’re usually sort of set at around 50%, but you can actually go, “I want to go up to 90% kind of certainty on this”. And when you do that, so for example, you’ve come back with this 0.8% of Finland, when you actually up the stringency, it goes down to 0.2. And when you look in that in more depth, it looks like what’s happening is you, you’re getting a bit of a match with somebody who’s in the database.

It’s giving you an average of fourth cousin, and this individual has got, uh, grandparents that come from Finland. And that is what I suspect  is giving you that tiny, tiny little Finnish bit, again. But that is such a small percentage that it could be that that matches actually, you know, once the database is updated, you don’t find that that match anymore. Um, also this person puts you at the level of on average being sort of great, great, great grand parental level that you would share, uh, a common ancestor. So, I would take that, that bit of potential Finnish ancestry with a little, with a, with a little pinch of salt. You’re basically coming back what we would expect you to, which is some 98%, 99% being, um, British and Irish ancestry.

There’s a really nice thing in that when you did a Y chromosome test and you look at the matches in that, you’re getting other people with the same surname as you. And that would be an interesting thing to look at. So, when you look at the, you know, you’re not getting perfect matches, but you’re getting, you know, a little, few little differences, but such that you would be expecting that there’s a really good chance that you share a common ancestor within the last sort of, you know, eight, 12 generations. So, it’s the sort of thing that, for that kind of thing, my first thing would be like, well, contact them and, and see if you can work out where your family trees match up, because you’ve got the same surname and very similar Y chromosome types. So, let’s, you know, you can follow that as a kind of a genetic genealogy thing.

You’ve also got some traits analysis, which came back and some of these are really quite fun. Um, I find, so let’s have a look at some of these ones…. So, you’ve got things like, do you have freckles? Um, did you have baby hair? And, and what they’re doing here is, is they’re looking not only at genes that they already know have been associated with particular traits through genetic studies, but they also have this ability, again, it’s having these huge numbers of people in a database, where they can not only look at their genomes, but they get them to fill in questionnaires. You know, what is your, what is your preference? Is it for salty or sweet? Do you prefer vanilla ice cream versus chocolate ice cream?… and things like this, and just having these sheer numbers of, of people with this kind of information allows them to sort of go, okay, well, it looks like it’s like those genome wide association studies, it looks like these bits of the genome might be associated with this. So, it’s allowing them to start to look at bits of the genome. Some of them may not be involved at all. Some of them actually may be involved and have an influence. But I mean, I really liked things like it gave you a wake-up time of…this is on days when you’re not working… 7:04 AM. I thought that was incredibly specific…

Ron McCullagh

And completely wrong it should be said!

Prof. Turi King

Is it?

Ron McCullagh

I’m afraid so.

Prof. Turi King

Yeah. We know that there are genes involved in, in our circadian rhythms and whether or not people are more likely to be sort of more of a morning person or more of an evening person. And we know that there’s, there’s numbers of genes that are, that are involved in that. They’ll also take into account, you know, how old are you, what sex are you this kind of thing when they’re, they’re kind of doing this sort of statistical analysis. So, you’re absolutely right -some of the stuff that they will be doing, won’t be right at all, but some of it will be kind of interesting. And Ooh, this is interesting. It’s allowing them to look at sort of particular regions of the genome that might be involved in, in particular thing.

So, they’ve got all kinds of things like, um, uh, whether or not you’ve got a bald spot or, you know, can you taste bitter things? So, we know that there’s genes involved in that. Are you more likely to get bunions? I mean, some of them, some of them are ones that you’ve just, you’re going to know by looking in the mirror, whether or not you’ve got light or dark hair…this kind of thing. Um, but other ones are kind of fun, uh, about whether or not… some people really don’t like the taste of cilantro, so coriander. So, it’s things like that, that they will actually, that they can, they can look at again, it’s a combination of genes that have been found through genetic studies and through being able to kind of look at these giant databases of genetics associated with particular traits.

Ron McCullagh

Yeah. It does feel very much that we’re, we’re sort of on a journey into the understanding of DNA and the detail that you’re giving back to me here. It’s, coruscating this in tiny detail… would you get a bunion? I mean, this is extraordinary that, that they have thought that, okay, there is a gene specifically associated with somebody’s likelihood of having a bunion.

Prof. Turi King

Well, they do think there might be a genetic component to bunions And presumably that will be genes that are involved in sort of bone growth and bone modeling that will be involved in that. But I, as I always kind of say, do take some of this with a pinch of salt, because, you know, presumably whether or not you get a bunion,  I’m not a doctor, I don’t know about this, but I’m presuming that whether or not you get a bunion is going to have something to do with whether or not, you know, the shoes that you’re wearing, for example. So, there’s the environmental factor as well. In, in all of these things, you know, you may grow up where genetically, it looks like you seem to be more likely to prefer salty things, but if something’s happened in your childhood, you may actually not like salty things. So it’s, I always say, take some of this stuff with a, with a pinch of…salt… (laughing)

Ron McCullagh

(Laughing)

Prof. Turi King

Um, but it is, it is fun. I do, I do really enjoy the fact that, um, genetics is becoming so popular. Some of it is a bit like, and I go, “Ooh, just take that, you know, carefully”, other ones are quite fun. And it can be, like I say, incredibly useful if you’re doing things like genetic genealogy. And I suppose one of the things that’s quite interesting now is that with the advent of sort of being able to do whole genomes, we are now able to do things like twin studies, but in a much, a greater level.

So studies of identical twins have always been very, very interesting because twins are known to be genetically pretty much… are thought to be genetically identical. And so, if you’re interested in things like personality traits, if you’re trying to go, well, how much of it is to do with the genes and how much is it to do with environment? By having twins and looking to see, well, you know, if they take, uh, you know, an IQ test, or if you’re looking at things like personality and they tend to be more on that, you can kind of go, okay, so that’s probably something to do with genetics.If it’s something whereby it doesn’t seem to have anything to do with… they’re very different then you can start to go, okay, so that’s presumably something that’s to do more with environment. And so that’s a way for how they look at, at, uh, traits, you know, sort of personality traits, uh, intelligence. And you have to be quite careful with this because obviously it’s things like IQ tests that are often the way that that intelligence is measured and there’ll be various things, um, that kind of come in to how well you do on IQ tests, but it is a measurement that people use of intelligence. But the other interesting thing is that you also have something known as it’s known as the Flynn effect. So, this is the fact that, um, people have been scoring better and better on IQ tests through the years.

And they think that obviously this is something that’s going to be to do with, you know, diet, education, uh, nutrition, all this kind of thing that, so it can’t be genetic if it’s happening that quickly. It’s environmental, there’s something going on in the environment. So, this is where twin studies have been quite an interesting thing. And actually now that we can do entire genomes, it’s actually been used in criminal cases. So, for example, um, in I think it was in around 2012, there were a series of rapes going on in the city of Marseille and the suspects were these twin men. And with standard genetic testing, you wouldn’t be able to tell them apart, but now with whole genomes, you can, because what happens is, is when the egg is fertilised with a single sperm, and then it starts to divide and it splits into two, what happens is each little embryo is going on his own little journey as the DNA is being copied to get passed down to the next cells. And it’s dividing and dividing and dividing and you start to get little mutations that are separate to each twin and being able to do this whole genome sequencing. Now, now it means that you can actually tell twins apart, genetically.

Ron McCullagh

 One thought I’m left with is, I worry that this, this whole story of DNA that’s been revealed to us of our own DNA, I worry that we’re going to think of it too much as our destiny and, and not, um, what it truly is, I think, which is sort of the scaffolding upon which our biology has been, uh, has emerged who we are, uh, and, and therefore will constrain us from being independent of thought and being creative and doing all the other things that, you know, we hope a great human life can, can do, and never feeling that DNA’s an anchor of some form.

Prof. Turi King

I think you’re absolutely right. I think if there is something that people can take away from this series it is exactly what you’re saying. Our DNA is like a scaffold to some extent. Um, and as I’ve kind of said, it, we’re not a blank slate when we are born, but we also write on that slate through our environment, what we do in our lives, we are not our DNA. DNA is not our destiny, who we are, is a combination of our DNA and our environment. So I think it’s really important to take away from this that you are a part of who you are. If you decide that you want to eat better, or, you know, despite what, you know, growing up, you might’ve had in your family and you decide, no, I want to, I want to change this now, or I’m going to take more exercise. I’m going to do more of this, or I’m going to, you have, um, you are an agent in your own destiny. Of course you are. So it’s, it is not just your DNA. It is what you do as well. And your environment that you’re in.

Sarah Fourcheraud

You’ve been listening to Decoding Nature’s Alphabet presented by Ron McCullagh and produced by me, Sarah Fourcheraud. In our next episode, Turi explains how Richard III, the last Plantagenet king of England, is now buried in Leicester Cathedral, rather than a carpark. To get transcripts, or contact us and say nice things, please visit our website www.expressivemindsmedia.com. If you’re enjoying these podcasts, please share to help us produce more. All our episodes are on Apple Podcasts or your favourite podcast platform.