Sir John Gurdon - Conversations with History

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(dramatic trumpet music) - Welcome to a Conversation with History. I'm Harry Kreisler of the Institute of International Studies. Our guest today is Professor Sir John Gurdon who is a researcher at the Wellcome Trust Cancer Research UK Gurdon Institute of Cancer and Developmental Biology. And he served as its first chairman from 1998 to 2001. He is a professor of cell biology in the University of Cambridge and he served as master of Magdalene College Cambridge from 1995 to 2002. In the spring of 2006, he is visiting the Berkeley Campus as the Hitchcock Lecturer. Professor Gurdon, welcome to Berkeley. - Thank you. - Where were you born and raised? - I was born in the southern part of England in a small village in the area where they expect people largely to be stockbrokers, though my family was not. - (laughs) And you chose not to be. Looking back, how do you think your parents shaped your thinking about the world? - Well, they were extremely supportive in the sense I was accorded private education. Not the state sector and it was actually better education that way which was rather expensive and they kindly provided that. So when the time came to aim for a particular career, my father thought the most appropriate thing would be a career in either the army or in the financial world, and arranged some introductions. But fortunately for me I was refused entry to the army for the National Service, a piece of good luck. I was actually a competitive squash player at the time and rather fit, but the family doctor decided I was not suitable for the army and diagnosed my slight cold as bronchitis. And that eliminated any possibility, thank heavens, of entering the army as a career. - So what did your parents think of your going into science? - Well my mother could always see that I was fascinated by biological things. Even at school I used to grow thousands of caterpillars to make moths to the intense annoyance of my tutor. But I had a sort of fascination for these things. And I think it was really her particularly who enabled me to switch from my education, which was completely non-scientific, into a scientific direction. - And you were identified early in your educational career as somebody who was not qualified for science, correct? - That's correct, yes. I have this rather amazing report, which roughly speaking says I was the worst student the biology master had ever taught. (Harry laughing) And he goes on to say that he had heard there was some possibility of me becoming interested in science, but this would be, to quote him, a total waste of time both on his part and on mine. And this whole whole idea should be immediately discouraged. - And at what level in your education did you get this news? - This was age 15, when I had done one first semester of science and that was the end of it, no more science from then on. Until later on when I was able to return to the subject. - And how did this affect you, your self-esteem, so to speak? - Yes, well it was, excuse me, it was sort of discouraging but curiously enough in retrospect, if you have bad teaching, which was in fact the case 'cause this was just after the World War, you're better off not being taught a subject badly and therefore come back to it when you can take it from a different point of view. So in a curious sort of way I see it as an advantage to have not had to do the dreary kind of school science that people did have to do at that time. - And I would imagine a key factor in being a good scientist is being able to stand on your own feet in a way, and go in new directions. - Yes I think that's right, I was, I had another piece of curious good fortune in a sense that I was extremely interested in insects and always have been. And I actually applied to do a PhD with the entomology department, but again, luckily for me I was refused as being a bad student. (Harry laughing) And then took up this embryology in effect with a very sympathetic person. So I moved into that slightly by default, but what a happy situation for me it was, because actually entomology in those days was a dull subject, there weren't really any scientific questions as there clearly are in development. - Many of the people I interview always talk often about doing what you want to do, really liking it, and it sounds like this was a ballast for you as you moved through different periods of your career because you really were drawn to the subject matter. - That's correct, I always had a fascination for it, and the interesting, thing is nowadays this, my career would have been impossible in the sense that I did classics, Greek, ancient Greek and Latin all my school time and then had to switch to science, and this involved my poor parents had to pay an extra year of private tuition to get into science and in those days they were actually short of students in Oxford and so I received this curious letter from the admissions tutor in Oxford that said they would accept me on two conditions. One was that I came into residence immediately, in a week's time, and the second was that I did not study the subject in which I had been examined. (Harry laughs) This is unimaginable at present. - So you were being ordered not to become a classicist. - Absolutely, they said I'm not suitable for that. And actually I later met the person socially, he was a man called Trevor-Roper who later became Lord Dacre and very involved in in the last days of Hitler. And he told me privately that his mind was on greater things and he'd realized he hadn't filled the places in the college and so he looked down the list of unsuitable people. - So I guess we can say that Fortuna is at work here. - Absolutely, a lot of it, great deal of it. - So what did you do your dissertation on? - My PhD dissertation, that was indeed on the subject I still work on, which is to say nuclear transplantation and that was thanks to my supervisor, a wonderful man who put me onto that as a very novel subject. It was practically rather a challenge because it, like everything, it didn't work at all at first, but he was persuasive and had ideas and it finally did so that was an extraordinary piece of good luck to be able to work with someone who was an outstanding mentor. - So you have become a developmental biologist, and I guess what I'm curious about how would you characterize the temperament and character required to do this kind of science? You've given us some hints already, perseverance is clearly one. - Yes, I think that's probably right because as all of us find, most of the things we try in the lab don't work, at least if they're at all innovative or novel they usually fail, and the question is do you keep at it or do you just say I'll try something else. And I think the, my feeling is you have to feel convinced it's an important problem. That may be the single most important thing to decide that if you could do it it really would be worth doing. And then one keeps at it and goes at it different angles, and finally some little unexpected result comes up which gives you a feeling of how you can make progress in that area. But I must say I was fortunate in having a complete fascination for both biological things and also doing things by hand. I used, when I was smaller out of amusement I used to make model sailing ships in the shell of a walnut. Just 'cause, doing micro things with hands has always appealed to me. - So it's a dealing with frustration experimenting, but of course in your work really working with microscopic entities. - In my case that's, really does appeal to me a great deal, and perhaps I'm rather bad at looking after the people in my lab in the sense that I do an awful lot of my own experiments myself by hand and they rather have to manage. But I like to hope that gives them some sort of help, the fact that one can usually do these things oneself. - Now you told us that you were a humanist become a scientist, and most people probably couldn't do that today so what sort of skills do you need, do you think? I mean chemistry, physics, what? - You mean to be a scientist or failed classicist? (Harry laughing) - Well, both, but let's do the scientist, yes. - [Sir John] What sort of science? - Yeah, but maybe the other is as interesting. - That's something interesting, too. Well, what do you need, I suppose, in a way I suppose you must have to have this inherent interest in something that you're trying to study. But one thing that was very prominent in my mind and in a way answers both those two questions, I thought if I'd spent my life as a classics person I would end up at the end of my career saying I've now achieved the level that everybody else has achieved for the last few hundred years. I wouldn't know more about Homer and Thucydides than anybody else. I might reach the same level, it wouldn't advance anything in human society in my view. Whereas in science you felt that at the end of a career you could actually see some genuine progress, both in understanding and in fact in practical use. So that was very much in my mind that one wants, I'd like to give my career to something where I can see at the end of it there's been a real advance. - And is there a root of that perception on your part, is that something you got in your early schooling from the humanities or from your parents? - No, from parents if anybody, maybe it was just sort of innate. Sort of thinking about one's future, one lives much of one's life by saying what am I going to do the next year and I often ask my, sometimes you have very bright students and I sometimes say to them, PhD students, where will you be in 40 years time? Most of them say I can't tell you, I'll tell you where I will be next year but I haven't any idea. In some ways it's a good thing to think what you, how your career might evolve if things go well. - Talk a little about this synergy between the individual scientist, his team of collaborators, and the broader scientific community. Because when we start talking about your work, it really needs to be placed in a tradition and with the work of others. - So maybe the comment to make is that in my time, and I think there's been a real change from the possibility of someone working almost as an individual as opposed to part of a team, and of course in physics my understanding is you work in enormous teams with big instrumentation. Things are moving that way, I think, in biological sciences. But I don't think they're going to be, ever exclude someone who explores novel ideas. It's rather easy now to get a grant for a huge piece of equipment and to have 10 people getting out lots, large amounts of data of sequences or something which you analyze. But I'd like to think there is still and will be for a while an opportunity to do things on a more individual scale, but not as much as there was. When I started you really could work as one person in a field and you wouldn't be worrying every day that you're going to read the results of your work in the paper next day. - So what then was the evolution of your research up until the 60s when you made a major discovery, which we will talk about in a second. What problems interested you after your dissertation, and where did they lead you? - Well, after my PhD dissertation my supervisor, my mentor said you should do something completely different. And that was right, and that's why I went to Cal Tech where I in fact worked on bacteriophage genetics. But interesting, to me I could never make it work at all. Every experiment I did failed completely. But I learnt an enormous amount by meeting a number of very interesting people, and the whole idea of how you do science became much more clear to me. So I went back again to what I'd been doing before, but in a more informed way. - What became clearer to you, if I may ask? - How you try to analyze things at a more molecular level, more detailed level, so I'm the... I'm the extreme opposite of the systems biology person who says we must look at everything, I actually can't. I look more and more down into, focus down on a tiny thing, to understand just one thing, and then try and enlarge afterwards. And I think it became clear after my year in Cal Tech how people can do, can make a molecular analysis. So if something happens in biology, the end result has to be that you understand it in terms of molecules, individual molecules doing something. And that was, my education didn't reveal that. For example, when I was a student we spent three days a week learning about paleontology. We had to learn every dinosaur bone that as far as I could see everyone at any one had dug up. But it wasn't really scientific, it was just a memory test. - So how did your work of transplanting a specialized cell into an E-nucleated egg, and then a tadpole emerge, how did that come about and what were its implications? 'Cause it was truly a revolutionary moment in developmental biology. - Right, so the background there is that the concept of using micro glass needles to move things around had actually been in operation since around 1900, when people, someone called Bataillon did some work of that kind. But the real advance took place when two people in this country called Briggs and King who were the first to be able to, within the vertebrates, take the nucleus out of a cell and put it into an egg. And it worked extraordinarily well. The odd thing is that a few years later they found that when they started doing this experiment with somewhat later stages of development, taking the nuclei from later cells, it didn't work really at all. Also my supervisor put me onto this, copied their work at a very early stage. And we were lucky in that it actually worked differently. And since the the more advanced the cell was from which you took the nucleus, you nevertheless ended up getting normal individuals. And that was really the breakthrough that made all the difference in my career, so that you ended up with an admittedly small number of completely normal individuals. When you take the nuclear site of an intestine cell, put it into an egg, you actually can end up with normal adult fertile animals, and that made me take a different view of this work from Briggs and King, who I greatly respected, and indeed if I'd had their results I'd have reached the same conclusion as them. But at first it led to quite a lot of controversy, I mean here was I just a graduate student sort of contesting the conclusions of two very highly respected workers. So naturally enough people didn't believe what I said, and I can see why. - What had they argued, Briggs and his colleague? - Right, right. Well they quite reasonably from their experiments had argued that as an embryo develops into a into a little later embryo in an organism, and at a very early stage the nucleus of those cells is no longer able to replace the egg and sperm that normally occupy the egg. And so the conclusion was that as development proceeds, the genetic material undergoes some kind of stable change which precludes it then substituting for the egg and sperm. That's a very fundamental question, and it has to do with whether, as we form from an egg, the genome so-called, the set of genes, remains constant or it doesn't. So it was it was a question which had interested scientists for at least fifty years before that, and this was really the first really good attempt to answer that question. - And may I ask what the animals were that you were dealing with, South African frogs, yeah. - Yes, it turns out that I was, for a odd reason, but there's quite a lot of history to how it came that a South African frog turned out to be a favored, one of the most favored organisms, which ultimately came down to the fact that someone had more children than they could afford to educate in England. So they went all around the world ending up in South Africa and finally ended up in England when the animal was used for human pregnancy tests. And the spare eggs were then of use to people doing developmental biology, so I used that. Now Briggs and King used the American frog, which turned out to be less good for these experiments. - So this a moment, a very important moment in the history of science, of the biological sciences. What was what was that feeling of creativity like, that wow when this happened? Could you really talk about, here you are tinkering, and I gather from what I've read that the really complicated thing here is taking the cell out and moving it around. So it's a very, somebody who's worked with delicate items like sailboats and walnuts you said, is prepped. Talk a little about that. I mean, the difficulty and then the aha moment. - Yes, so that that was an early event in my PhD work was to attempt this experiment which got, as I say, completely failed. And the most obvious reason why it failed was that when you used a micro glass needle to put into the egg, you could push it in and it came out the other end but it actually hadn't entered the cell at all. It had taken the membranes with it, pushed the whole lot through out the other end and come back. And it turned out to be impossible to get through this very viscous jelly, so that was the first major problem. And that was solved largely by the fact that my mentor had recently got a grant for a new microscope, which had nothing to do with this work, it was for an ultraviolet microscope. And we discovered more by chance than anything else that it happened to emit light of a wavelength that dissolved this elastic jelly. As it happens, it also killed the resident nucleus, so it was a extraordinary piece of good fortune that that worked. And that then, suddenly things started developing, you found that you could do the experiment. And that was a key point, if that had went on and continued to fail, I really don't quite know where one would have gone. - But talk a little about your feelings, about that aha moment when this, I guess what you got was a mature, you got a tadpole, right? - You've got a tadpole, that's absolutely right. - Right, right. - That's right. - When previously nothing happened at all, suddenly this thing. So the next you thought, well this is amazing, could it actually be right, that's the thing one always thinks, even at my stage. Whenever you get a result you think, could there be an artifact? And there was an obvious artifact and that would be that the resident female nucleus in that egg had not been destroyed, and all you've done by pushing a needle in was to somehow activate that. So we needed a way of proving that that was a rare result. And then another piece of, partly good fortune, partly wisdom of my mentor came about. He had a student who is doing some completely different experiments, and they failed too, for an odd reason. Instead of him saying well, do something else, he said there must be reason why these are failing. So he discovered what turned out to be a exceedingly important mutation, which acted as a genetic marker. And so we could put in the nucleus of one cell which was genetically marked into this egg, grow the embryo up, and prove that the embryo carried that genetic marker appropriate to the nucleus you put in, and not appropriate to the resident nucleus that you hope to have removed. And that was I think really why it was that the general scientific public believed our results. They probably wouldn't have done otherwise. So that was very important. - Now in terms of science, this was a very, a real turning point in the road that led to the cloning of Dolly many years later. And I wanna help our audience understand this. So what you had, you won the Copley medal, which recognized your work that had given decisive evidence that specialized cells are genetically equivalent, and they differ only in the genes they express and not the genes that they contain, explain that. - It's a very precise and accurate statement. So the idea, just going back a little is that after, particularly after the results of Briggs and King, the thought was that the nucleus or the collection of genes we have would actually change as the egg develops into different cells. So our skin, intestine, brain, blood and muscle would all have different sets of genes. Because they would lose the ones that you no longer need. So the, for example the skin cells don't need brain genes. And indeed it was an idea of someone in the 1880s called Weissman that that's indeed how development worked. It was a plausible idea, as the egg develops it sheds off these genes, and so as the cell decides to follow a particular pathway, that's a very neat way of doing it. You get rid of the genes. And so it gets narrowed down to that fate. And the really important thing about this question and the experiments was that that turns out not to be the case. So all our cells with very minor exceptions contain the same set of genes. And I would say that's fundamental in any kind of cell replacement therapy which we might envisage. And indeed, obviously if that had not been true Dolly the sheep could not have been formed. But it turns out it is that way, and so what we now understand (coughs) excuse me, is that as cells develop they contain the same set of genes. The only difference is that something decided to read the skin genes in skin, and brain genes in brain. So that's what they meant by expression in that statement. - Now why did it take so long, because we're talking about a 30 year interval, really. Your experiment was in what year? - Well the first time we got an adult, a successful adult it was 1958. - [Harry] Oh, really, oh, okay. So why so long? - Yes, very good question and I've wondered about that, too, and I've tried to explore that. Now, one reason for that was that (clears throat) excuse me, when they were doing these experiments of mammals, and I might have stared that I had a PhD student in early 1960s who did indeed try transplanting nuclei in rabbits. And it didn't work or at least not significantly well. And then that got left aside, now why? And the reason is that someone called Davel Salto took this up very seriously and did a lot of experiments, and he found that you the best you could do was take a nucleus out of a two cell embryo and put it back into a one cell embryo. If you did anything else, anything further they didn't work. Now it turns out the explanation is that if you put, transplant a nucleus into a fertilized egg, an activated egg that's already started, it's extremely difficult to do and it doesn't like to receive that nucleus. We had always chosen to do experiments using un-activated eggs, they're sort of naive and waiting to go. And for reasons that I'm only partly clear about, that was not done in the early mammal work. They felt that a better route would be to, and they had reasons for doing that, to thinking of going into the fertilized egg, but it essentially doesn't work. And Davel Salto did, it was very careful experiments published through very good journalists explaining that that this particular route he used does not work, and indeed it doesn't. But switching back to the route that was done with amphibia it actually does work, and that's how Dolly the sheep came to be successful. So it's not entirely clear to me why they wouldn't have tried that, I think it was technically more difficult. But that seems to be the explanation so you're quite right, it took about forty years for this essentially similar result, in many respects, to be obtained. - And I gather it was really out of industrial experimentation as opposed to coming out of university science, is that -- - Dolly the sheep? - Yes, yeah. - Well I'm not so sure that that's right, I don't really know whether perhaps that is, never really asked, it came out of an institute that had a lot of industrial support called the Roslin Institute, but it wasn't, I don't believe that they were really being told we we want you to do this work because it's going to be profitable. I don't think there was a perceived profit, it was more that it was exploratory work with animals. Hence the sheep, not a mouse. - So what what directions then did your research take after this, help us understand that and we'll talk a little about what you were lecturing about here at Berkeley. - Yes, right, well the, I mean if we, we could say it this way, that my only results tell me that actually the way development works, and that was the fundamental question I've always been interested in, interested how does an egg make an animal? It's an extraordinary process, I should just emphasize, because this egg has no, no one tells it what to do. Just one cell and somehow it knows how to make an animal, so how is that? Well, we were satisfied then that that's not by any loss of genes, the genes are there, so something must read the genes, decide which genes to to read and which ones not to. That then took me off in a number of directions, much of which I talked about yesterday, which is what kind of thing tells the cell that it must read one gene not another, and that was how we got into what I call morphogen gradients, signals that come from another cell and say, I want you now to read that gene not another one. And that then was a large part of my mid-career, and dealt with the morphogen gradients, community effects, signaling and so on. And then much more recently I've gone right back to the original question of how is a transplanted nucleus reprogrammed? What I'm going to be talking about today. And I see that as all connected, it's all the same question. Just going off one direction and then coming back to the same one, perhaps another direction, it's all going back to the same question to try and understand ultimately how this happens. - Yesterday I noticed, and now that I know you were a classicist, you, I think the headline on the slide you were showing was cell commitment to future development, so let's talk a little about that. Because what you were telling us, and were really four ways that a cell after formation would would commit to a path of development, what are those four elements? - Yes, well one of the things which you certainly absorb very well, and which I refer to again today is this surprising fact that when the cell begins to set out on its on its career and pathway to become something like skin or muscle, at an amazingly early stage it refuses to change direction. Even within a matter of hours, that says I'm going in this direction, I'm not going to go any other direction. And as long as I'm left as a whole cell, so inside that cell it's sort of re-instructing itself to keep going in this direction, won't take another pathway. And the point that I will make today is that if you then take that cell apart and take the nucleus away, then it's completely happy to change direction. So it's a surprising contrast between a whole cell, which is committed to a particular pathway, hence commitment, as opposed to the individual parts of the cell which are not. - Now in this initial process, I think you identified four elements that said it's on this path. To repeat them, that the pre-fertilization controlled development, asymmetric cell division, signaling between cells, and then what you call a community effect. Summarize that for our television audience. In other, so what you have is a set of processes at work that say you're going this way, fella. - Yes, that's right, that's exactly right, what you say. And the, in a way surprising thing is, (clears throat) excuse me, this egg which is, you know, we we eat a chicken's egg or see frog eggs. But the egg before it's received a new sperm already has a fair amount of information in it. In fact it's taken, in many cases as much as a year to make that egg from us very specialized cell, and that already is a part of the whole of our life, is determined before fertilization. So that's point one, and then the the other thing is I emphasize, but this asymmetric division is a way of again telling cells to choose one pathway as opposed to another. And then of overall importance is this signaling by which a cell receives molecules telling it in which way to go, of which the community factors are variant. So it's a progressive process, and I think that's a logical way of viewing it, with four steps that are fundamentally responsible for deriving a thing like a heart or brain cell from an egg. - Now, either the humanist in you made the comparison between the phrase... faith hope and charity, and of these the most important is charity. And you turn that around to say space, time, and concentration, and with concentration being the most important. - That's right. - So these are the factors that set us on this course. - Yes, I've increasingly become intrigued with how precisely things work, so let me give you an example. There's a phrase called haploinsufficiency syndrome. Now, all that means is that you and I have one gene inherited from our mother and one from our father, so we have two genes that should do the same thing. Sometimes things go wrong, and one of them isn't any good, so we only have one. Now amazingly in a number of cases, if you have one copy of a gene instead of two, things go wrong. Now that means that a factor of two difference makes an enormous difference, and indeed other experiments are referred to, so factors of three make a huge difference. So everything in us is regulated to an extraordinarily precise degree in actually concentration. And that when you go into this in detail, as much of my career has been involved, it turns out that that's the single most pivotal component in making things work the way we do, is the concentration of things. So that was why I chose to emphasize that point. - Talk a little about this reverse process which you're gonna be talking about this evening. I haven't had the fortune yet to hear that lecture but what then becomes the implication for all this work in stem cells of what we might achieve with that. - Yes well what I will be saying is that if you take the nucleus genetic material out of one of these cells that are quite clearly committed, they know what they're going to do and nothing will change it. But you take that nucleus out and put it into the egg, then that essentially rejuvenates that nucleus in most cases and what I'll show is that you can take a cell from an adult put it through this process and it then essentially forgets everything it knew about following that pathway and starts life again. And there are things called stem cell genes, genes which mark the fact that it's gone back to the beginning of life again. And so that in a sense creates a stem cell, because if you go right back to the beginning of development the ultimate stem cell is an egg, because it can form everything at all. It's totally potent. And you recreate these sort of universal stem cells by this procedure, so that's what I refer to my talk as, from egg to adult and back again. Take it right back to the beginning again. And of course if we could make that work really efficiently, I do believe this would give the opportunity for cell replacement in humans. - So that one could use one's own materials to actually make repairs. - That's absolutely correct. - Right. - Yeah, that's right. - And the key thing which I haven't said yet is that in terms of replacement, all of us eventually would welcome some replacement of parts. You really like to have cells of your own genetic constitution, so you can receive cells from other people but you may know that if you do, you have to be subjected to what's called immunosuppression. It means you can't reject the cells and of course you also can't reject any infections that you get. So immuno-suppressed people are quite disadvantaged. In an ideal world, we would give ourselves rejuvenated cells of our own genetic constitution. And this, whatever you call it, cloning or anything like that, that is actually the only efficient way in which you can hope to derive rejuvenated embryonic cells from your own adult cells. - Now what are the big obstacles to achieving this in, within terms of a lack of information, or what? - Right, so the big obstacle is that it works, but not very well. That's the fact of the matter. And so when you do this, you sometimes get amazing results, like I mentioned the adult animal derived from an embryo cell or Dolly the sheep derived from mammary glands, spectacular, and it can work, but the efficiency with which it works is actually extremely low. And that is the reason why my own work for example is completely committed now to trying to understand the mechanism, molecular mechanism of how it is that you rejuvenate a nucleus, send it back to the beginning again. 'Cause my view is that only if we really understand that mechanism, can we hope to make this work efficiently enough to actually be useful in a therapeutic sense. - I wanna go back to this earlier career of you as a humanist, which you turned away from because this is really, this work is raising a lot of sort of big questions about who we are and where we might go and so on. How do you think about that, or is it part of the professional list of a scientist not to focus on those questions? - Well I do think about it, and I shall say a bit about that today, but my own view in short is that there's completely unjustifiable concern on these issues, people talk about the ethics of this. And they would say for example that if you transplant the nucleus of one of your skin cells into a donated egg from some woman, this will form an early, very early embryo, and it would. And they say that is a potential human life. I would completely disagree with that on the grounds that it is not a potential human life in the absence of implantation, a key step in mammalian development. So I see this rather skeptical where people who are in good health, in high places, whether they're lawyers or whatever sitting there and saying, I'm fine, but I don't like you to do these experiments which might in fact greatly improve the health of other people. So I find that quite an unacceptable philosophy. So I would say this early human embryo is actually not a potential life and has no significant validity. I don't think it may or may not have a soul, it doesn't matter, The fact is it's not going to, you're not killing anything that's significant, and if you don't do it you're then not taking advantage in the way that we could of relieving an awful lot of human suffering. - So it is that practical application and the intention here of the good that might be done that should define the process. Are there things that we should worry about in this process that might get out of control, and that is that, what is your insight on that problem? - Yes, well I, at the end of my talk today I shall go through five reasons why people might object to that. And one of the ones which I find particularly unpersuasive is what I call the thin end of the wedge argument. So they say you scientists are doing this kind of thing, that's okay, but they say we don't know what you'll do next, we'd better stop it quickly before anything worse happens. It's a very bad argument, and I shall go through these points, and I don't think any of them have any worthwhile validity, to be honest. - And how do you see the the commercialization of this, these insights ultimately being achieved? Will the scientific breakthrough lead the market to see the implications, and then it will happen in a broader scale? - Well that's an interesting question of whether there will be commercial gain from this kind. Let's assume the technology, like most, improves, people find out how to do a thing and it works better. It's unclear to me how commercially useful that will be. The end point of my work that I'm currently engaged in, if it were to go well, would be to understand what molecules you need to rejuvenate a nucleus and create a universal stem cell. So now if that was some special molecule which I could put a patent or patent on, maybe there'd be money in that but I rather doubt if it will work that way. So I'm not sure that there is going to be a huge commercial consequence of this work, however successful it might be. - What would be your advice to students as they prepare for their future? Your career stands out as one where rejection paid off once you chose to do what you wanted to do. - Yes, I'm very troubled that every now and then one has extremely gifted PhD students, and I'm lucky enough to have those from time to time, and almost without exception the recent ones have all given up science and gone into the finance world. I regret that, and I'd like to say to them, consider yourselves at the end of your career. You will have probably made a large amount of money and you'll have an expensive car and a big house and you can take holidays wherever you want, but is that really what you want out of your life, or would you rather say that what you've been able to do is to make a real difference to the quality of human life by relieving suffering, in the way that centuries later they say oh you know, Dr. Chrysler, you actually did some of this work which was really helped the whole of human society rather than, you have actually made enough money to live comfortably. So I would hope that progressively, people will be prepared to see, look at their life as a whole and look at the end point, other than in simply financial terms. And when I was young that was, the scientific career was regarded, highly regarded as a good career. and I think it's unfortunately less so now largely because it's very poorly rewarded, at least in Europe, financially. So he will have to suffer. But in the long run that will probably change. - What, looking down the road, should we be, the general public be watching for in terms of milestones, are there certain questions out there that in this work that you're describing we hope to be getting the answers from? - Now, do you mean what they should be looking towards as a positive effect -- - [Harry] Yeah, yeah, yeah, right. - Not worrying about a negative effect. - Yes, right, worrying about a positive, yes, yeah yeah yeah. - Looking about the positive, what can they hope for. - In other words in this realm of questions that you're dealing with, some, a couple of questions, or one that stands out that needs to be answered in the next stage to achieve these positive developments? - Well in my opinion the single most important steps will be to understand how this rejuvenation process actually works. And we and others are beginning to pick away at that problem and to give you some feeling for it, we have to know what it is that removes the marks, as they're called, that make a a set of genes specialized. So as you have your cells becoming, say, skin cells, they actually switch off, as we've said, the genes needed for the brain. They're there, but they're not very easily activatable, and they acquire marks which for example they're called methylation of DNA is one such thing. And we know actually nothing at the moment about how that is reversed. It is reversed, I have no idea how it's done so. But if it isn't reversed it won't, the whole process won't work. So you can divide the whole process into a few steps like that, and I think that's what we would be watching for to see as people gradually find a way of reversing these marks, that gets it back the beginning again, and then of course you have to start telling it in which direction to go after that. But this reversal process is undoubtedly complicated, but I'm quite sure it will be eventually worked out, and those are the steps which were ultimately, if it really works well, just to give you a feeling for this I would say eventually we should be able to take a skin cell and apply these molecules, which we by then would have found out what they are, to that skin cell to directly switch it back into an embryonic cell, from which you can derive heart muscle brain and so on. So that's the ultimate vision one would have of this. - And then one final question, where do you think the leadership will be in in these new directions, do you think the politics of some countries, unnamed, will affect its future leadership role? Because although in your mind a lot of these ethical issues are resolved, they have become political issues in some countries. - So I would doubt whether the constraints or restrictions which do apply in this country and even more in some others are really holding up progress significantly at the moment. It's unrealistic to do experiments with human eggs, just an inefficient way of doing it. And once you know how a thing works in a mouse egg or even in a fish or frog egg, the principles usually turn out to be similar. So if we really knew how it worked in a mouse, for example, it wouldn't be that difficult to switch over to humans, and I would assume that by then any public concern will have evaporated. Let me give an example, it was the in-vitro fertilization, as we call it, was invented primarily by Bob Edwards in Britain, as it happens, and the first two years when he did it he got terrible abuse, bad press, letters of people threatening his life, etc, For all sorts of, they said unnatural, we don't like this. But in a couple of years it turned out to be very useful. And the whole thing's completely forgotten. So I think what will happen in the world is people will realize that this is a really valuable kind of direction to follow, and these reservations will just evaporate. - Sir John, on that hopeful note I want to thank you very much for taking the time to be here today and thank you for delivering the Hitchcock lectures on the campus, thank you. - Thank you very much for your interesting questions and discussion. - And thank you very much for joining us for this Conversation with History. (dramatic electronic music)
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Channel: University of California Television (UCTV)
Views: 8,189
Rating: undefined out of 5
Keywords: cells, research, science, biology
Id: iiS36VjFrcc
Channel Id: undefined
Length: 47min 8sec (2828 seconds)
Published: Thu Jan 03 2008
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