Incest and Folk-Dancing: Two things to be avoided - Professor Steve Jones

good evening ladies and gentlemen I'm Roderick flavin I'm the Provost of Gresham College and it's a great pleasure for the second time that today this is our lecture program is expanding for the second time today to welcome an audience to Gresham College we have the great pleasure this evening of having somebody who wasn't on the program but who volunteered to give us a lecture this evening and we of course accepted with enthusiasm and alacrity and it's interesting to see from the perspective of publicizing the college how word of mouth and the website can produce the kinds of audience which I'm sure Steve Jones is always used to but it's very nice that he's here this evening and of course that he will be lecturing here this evening this will be recorded as usual and therefore will go on to the Gresham website and worldwide as our lectures are now going and that's very appropriate because he is somebody with an international reputation emeritus professor of genetics at University College London and of course particular focus of work on evolution and in particular on snails he's won many prizes the Faraday prize of the Royal Society the Owen prize for secularist of the year and he's worked very well-known I'm sure to all of you for his lucid exposition of science and in particular of genetics and other aspects of his subject so we're really delighted to have him here this evening to talk about incest and folk dancing to things to be avoided thanks for that the first line of the United States Army's mule training manual is alleged to say to gain the animals attention first strike it smartly between the ears with a stout stick and that's why I chose this title incest in folk dancing I say to my students at UCL in their first genetics lecture that I'm a geneticist and my job is to make sex boring and it'll blank at me but after 24 lectures they know exactly what I mean and perhaps I'll persuade you that both incest and folk dancing I don't necessarily fit into that context the quote comes from that gentleman here so who's a Sir Thomas Beecham okay was actually strange enough for not very far away from here and he once wrote that everybody should try anything everything wants except incest and folk dancing and that's because he hated the music for percy grainger remember to get a lot of English folk music they also said incidentally everything in music has its place even a brass band but its place is in the open air and 20 miles away so let something to talk about I'm going to go light on the folk dancing with heavy on the incest okay an incest of course involves some mating between two individuals who are related to each other in the legal sense perhaps between brothers and sisters but in the wider sense it involves every mating that's ever taken place in every species including ourselves simply because the simple pressure of numbers means that we are in fact all relatives and to understand what incest means you need first of all to understand what sex is what okay what's that what's the difference between males and females and what does the act of sexual reproduction actually do well everybody thinks they know what maleness and femaleness there and this is an image of what every man of course really wants to be this is a really a Steve Jones it's not me listen to that really was the Pan Pacific bodybuilding champion a student once came up to me after showing this and looked very concerned said have you not been well professor Julie but you'll see this is the image of what maleness is in the popular mind the guy's extraordinarily muscular rather dim looking sort of petulant or expression on his for angry expression on his face maybe searching for a mate impressive posing pouch and that might well summarize what maleness might be and to some extent that's accurate because if you go elsewhere in the animal world you find just the same kind of pattern he has a male sea elephant or elephant seal the same thing and this is a species which is found in around the Pacific and in the Antarctic and the males are about five times bigger than the females only one male in five makes it to be adult because four out of five are killed by the other males as they fight over access to females and only one male in 20 of those that are born actually succeeds in having offspring that work was done by a friend of mine with a paternity testing system and a long pole and a sharp stick so he said he died there I saw that what that tells you that this in this animal puts a huge amount of effort into being male and attracting females okay he's also typically male in the sense that he's not being very intelligent about him because he's wasting his effort on water penguins which isn't going to do his genetic prospects exactly look good okay so that's one sense of what maleness means but actually it's a there are deeper senses than that both of sea elephants and Steve Jones this Steve Jones and lad Steve Jones are filled with this rather noxious chemical that's called testosterone and the other Steve Jones mic possibly and I don't wish to libel this under him have more than most of us okay so that's testosterone and testosterone it's dangerous stuff it's actually it's it so it does many things it makes you male but it does terrible things to your life expectancy this is the patterns of life and death of men and women men in blue women in red and you can see top right top left there that there's a higher mortality rate of men than women bodybuilders who abuse testosterone I'm sure that Steve Jones does not do that bodybuilders who abuse testosterone actually tend to die for very masculine reasons die young car crashes pursue murder-suicide all those male things accidental death is common if you look at the bottom left you can see even for a five-year-old by the death rate through accidents it is about twice what it is in women look a five-year-old girl a little known that accurate fact of modern science is that men are struck by lightning at three times the rate of women now you may doubt that but it's actually true but why should that be it's because they're being men they're out on a golf course or whitening conductor in their hand showing off being masculine and being frazzled as a result men are murdered at ten times the rate of women and men actually murder of ten times the rate of wind rather more surprisingly maybe invested nearly at the bottom on the bottom right the men are much worse at dealing with parasites and infectious diseases than women now because Lester on testosterone suppresses the immune system so you might argue then that that's what maleness is it's a it's a system that makes Mex males unlike females large angry violent and suicidal okay well yes but yes but because that actually is only a very small part of the whole story it is much more typical female it turns out that in the animal world as a whole generally speaking females are bigger than males that's true for many many creatures and this is not an extreme example this is a thing called the anglerfish which for many years was thought to be a entirely female thought to be a path in a gem just to produce just a police officer me without males and then it was discovered that actually there are males the males are these small creatures that are ringing their way into the affections of the female and what the male actually does attack it attaches itself to the female attaches itself to her blood supply and reduces itself to us to being a sack of guts and genitals what more could any male want more Canadian and the female is decorated with half a dozen or more males and she chooses in a way that we simply don't know one of them to donate sperm and then she and then she produces offspring in a sexual way so size doesn't doesn't give you the cue the clue may be genes tell you something about what it means to be melt well we all know that men have a particular chromosome the white chromosome which has been read from end to end and I don't want to bore you with too many details it turns out to be very extraordinary chromosome it's much reduced and battered and badly damaged version of what was once an X chromosome the female chromosome females have two x's males have an X and a much damaged why it has an amazing on the structure parts of it had been moved from the X in the recent past they're called the X transpose the pinkish ones the most amazing things are those pale those those pale blue ones that are called amplicons and what that is what they are are palindromes now we all know what a palindrome is a man a plan a Canal Panama if I say that backwards a man a plan a Canal Panama it needs the same because it reads the same left-to-right point to that what these pump things are a length of DNA about five million letters law which read AGC CCT TCG CAF so of the five million for two and a half million letters and then immediately switch and read the you need a mirror image going the other way and why that is - we have no idea so you might argue that that's what maleness is it has to do with having a white chromosome but even that doesn't work um because there are plenty of creatures that manage to be male without having any genetic differences at all there's a fish that does that and I'm not obsessed with fish this is a North American fish called a blue fin dress okay and I guess you can see which one's the male on the bottom the one with the showy tail and the big pectoral fin and these fish live in groups what happens is that one male so harasses a bunch of a dozen or so females and tries to fight other males off usually doesn't succeed although you might think he succeeded again DNA testing gives you some rather surprising results but and bring them into the lab or into the aquarium and you could put these animals into a tank and remove the mail well understandably there's a moment of chaos and despair when the mail has gone but after a day or so one of the females begins to look rather shifty and she turns into a mouth fully functional male and produces sperm and fertilizes her erstwhile sisters and that's actually sex determination by embarrassment by social pressure what actually happens is that the dominant female the one that's most aggressive undergoes a hormonal shift that makes a man that might seem odd but it's not odd really because we all know that humans under intense social pressure often undergo quite big quite big young hormonal shifts including hormone shifts in me or not a lot of sex hormones so you don't need genes to be male okay well what's the true definition of maleness and femaleness and actually it will bring us towards this notion of of incest and inbreeding it turns on differences in the size and differences in the size of sperm and egg we all know that that sperm are much smaller than eggs in fact every time a man has sex he he makes enough sperm to fertilize every woman in Europe which is another terrifying thought and when I was writing I writing a book on on men at one time and there's a good general rule that if you ever write a popular science book with figures or numbers in it you have to give some analogy or parallel what have you and so I wanted how can I in a straight the amazing abundance of male sex cells compared to female well turn to the World Health Organization which tells me Adam certainly wouldn't lie that there are about 50,000 million copulation events in the human population each year a simple sum takes you down to about that down to about a million litres of semen everyday glam Ethel that's a lot the men of the world make a million litres of semen every day I wrote with a vivid a flow equivalent to that of the River Thames at Westminster okay so I thought that was pretty good the book got to print got to proof staged and Oscar Wilde once famously said I do not start writing until I get the proofs and I thought I better just check a few facts now that it's in proof so I looked at that bloody hell that's a lot of water coming down that river so so I wrote to Thames Water explaining why I needed the information and there was a rather stunned silence but Africa after a week or so they was letter from the head of Thames Water which said do presume thank you for your letter we have had many complaints about water quality good maybe this way but in but in fact you you quite misunderstanding of the flow of the Thames 15 billion 15 million litres a day is equivalent not to the Thames at Westminster but to the Thames a few miles from its source so we thought that much in terms of volume but in terms of cells it's quite astonishing there are every second five births across the world so that since I started about two or three thousand babies have been born across the world and every second if you do another sum you can work out that the men of the world make about two hundred thousand billion sperm so for five births two hundred thousand billion sperm every second every second the women of the world make four hundred eggs okay so there's an absolutely spectacular difference in the mating strategies or males and females and that is the definition of what female is she has large rare sex cells males have small and common successes and that's almost biologists full of exceptions but that's almost the entire that the universal definition it isn't always true there are some very bizarre exceptions which are we don't fully understand there's this huge difference in size between human sex cells there's a fruit fly which I once worked on we saw followed by flicker which has ice which makes a single sperm every time it has sex and it's about it's longer than its own body it's about a thousand was longer than human sperm and that would be equivalent in the human context to a man making a sperm the height of Nelson's column which is rather terrifying thought I think you look great okay so that's it it turns out that's it therefore when we look at sex there are very few general rules which apply across the whole piece when you come from the top down you look at men and women or the way that sex is determined or there would be the the sexual strategies of sperm and egg and you can pick up exceptions everywhere so what happens if we look not at the biology but at the arithmetic from the front from the bottom up and the univer T of sex really which is universal and is unexplained by biology is that it's a system whereby every individual has about has two parents now when you think about others extremely surprising we every female every sexual female every time she reproduces is forced to copy the genes of another individual male partner and she's forced to dilute her efforts by copying those genes now we know that in terms of of evolution a difference in success of copying genes of the few tenths of 1% can have massive effects over the years and a difference in success or reduction in success of 50% in fact more than 50% that should mean that sex is basically too expensive to get to indulging but it's not it seems to be universal so there must be some quite powerful force behind it the force is actually that the mechanism which generates and preserves genetic diversity perhaps the most extraordinary finding of the human genome project which has been much overhyped but is finally beginning to do a little bit that's interesting it hasn't done much so far but the big surprise was to find that genuinely was a surprise how much genetic variation there is in the human population as I say to myself that's right if you sequence along the human sequence among the human genome about one site in a thousand across the 3,000 million elements of the human genome is likely to differ between you and the person next year okay now what sucks does is to reshuffle those differences every generation it turns life into a game of poker rather than a lottery you reshuffle you your genes when males and females you make new combinations every generation now that means that everybody in the world unless you happen to be an identical twin and as it happens my mother was an identical twin although I don't think that's why I became a geneticist you're different from everybody in the world now absolutely what's more you're different from every human being who ever has lived or ever will live genetically and what's even more every sperm and every egg ever made in human history is different from all the others and that's what sex does it maintains massive amounts of genetic diversity we kind of know why that diversities that has to do with the need to escape to give flexibility and allow animals to evolve rapidly in the face of external pressures from disease from climate from starvation and the like but what sex does is maintain diversity and if you don't have enough sex you don't have sex at all you commit incest then you as we will see the amount of diversity begins to go down very quickly often with rather dire and results okay now everybody has got two parents okay so that must mean of course that everybody's got four grandparents eight great-grandparents sixteen great-great grandparents and so on but that isn't true for simple arithmetic reasons and you can illustrate that again perhaps with another metaphor from the non scientific world is beautiful William Blake drawing of the apocalypse okay and we all know about the apocalypse it's almost honest when we removed when we when we leave a couple when we leave the European Union know that and what the apocalypse consisted on for Blake and for many believers was the moment at the end of time which would when we know what he was sure but probably sooner rather than later the end of time but everybody who had ever tymberlee on earth and everybody who had a ballot would be gathered together and judged and a very few William Blake probably included would go to heaven and the rest of you would burn in the eternal fiery pit okay and you can look into the history of that and it has a clear historical resonance to do with this place here which is the city of Megiddo in northern Israel this is an ancient city which was which was a subunit people have been that an extraordinary place and in 722 BC in Old Testament times time of the great battles given in the Book of Kings and the southern twenty-two BC Sargon there was the head of the Assyrians who raided the place destroyed it killed most of its inhabitants and expelled the rest and the rest became the twelve Lost Tribes of Israel but the descendants are generated the myth that one day they would get back to mega GaN Armageddon okay Megiddo for the word comes from and they would assemble on the plains of Megiddo and they would get their just deserts they would be judged and Ferrum not to be wanting and they go to have nobody else with burn okay so what you can do a sum you can ask how many how many people will be there if that actually happened 2 4 8 16 32 64 hundred 28 and so on if we say we're going but we're going back perhaps 30 or so generations on modern Latin by a hundred or so generations for that date you get to a sum which is extraordinary if everybody did have two four eight 16 32 and so on ancestors a purely sexual population the world population who would assemble at Megiddo would be a ball of people solid ball people the size of the earth and expanding at the speed of light okay so in the fact that there are certainly six billion of us rather than trillions of trillions and suggests actually that we're not as sexual as we think we are if we define our sex as having two parents four eight sixteen we are forced by the simple power of numbers to realize that everybody is the offspring of incest managed between relatives at some relatively recent time in the past you could the guy who did who there's the son the guy who discovered that was Francis Galton versus golden as many of you know was Charles Darwin's cousin and he wrote a book called hereditary genius which is sometimes hailed as the first textbook of human genetics and I think that's a bit unreasonable if you agree that it's a very odd and highly politicized volume but Jo the golden was there was a genuine genius there's no question of it unlike Darwin it was both a genius and an effective and thoughtful and cowardly person gone Tom was a genius but he was highly ineffective he started all kinds of things off and he never really finished them but he's an important figure he more or less founded modern statistics um he was interested overwhelmingly in human quality and he was convinced that that intelligence on run in families he was I hear worked on human Beauty and UCL we still have and he left his money to use the old to found the first chair next to human genetics department in the world at UCL we still have a little brass counting device which he held in the palm of his hand and walked around British cities scouring the local females on a five-point scale from attractive to repulsive and that might seem to you all but it's a measure of quality I've tried this with students people have tried it often tried it and it's it works everybody agrees both male and female who was attractive and who was repulsive in the opposite sex so it's some measure of quality but from our point of view the thing either that was particularly clever was to work out the consequences of inbreeding Dalton who was a rich man not as rich is Darwin who was worth about 17 million pounds in modern terms when he died Gordon was a rich man in the 1880s he used to go on walking tours on in the Italian part Italian speaking part of Switzerland and it was then a remote part of the world almost nobody went there as poverty-stricken some things have changed and he'd turned up one year in average and settled in and he noted something very old prepare yourself for crushingly week joke he noticed that everybody in that village had the same surname you might have been shall we say spaghetti okay so the entered his mind didn't think much of it climbed the next day 20 miles over the mountains to the next ice that had very settled in there notice something very odd again everybody in that village had the same surname but it's a different one it was pasta next village cannelloni next village farfel only and until you run out of Italian the farinaceous foods and he first he thought was fascinating there must be some advantage to being called them spaghetti in village one and pasta and illage to what could it possibly be but then he realized this was the result of these populations being not being completely sexual because they were very small and isolated from each other I selected from each other and if he way he went into the wretched into the records of each village and he found to simplify the story but actually five hundred or six years earlier each village have had ten names in it but every generation if any male has no sons he has no daughters he has door only daughters of no children the talk then his name will disappear and arbitrarily one name will take over and that process is really very powerful and what we can do here we've got a system of of a population with 22 for some random reason 22 individuals in it but we're talking males here 22 men in a population of 18 of them in the previous generation had have had had sons 16 in the previous one and we can go back back back back back until we get back to about 15 or so generations previously where we have one male who is actually literally the atom of this present population the first mr. spaghetti there is okay whoops mom where are we here first mr. spaghetti is the most recent common ancestor okay MRCA as he's known and all the males at the bottom here are his descendants now so Adam really existed Adam existed on a global scale on a village girl and I'm a global scale but of course at the time of that most recent common ancestor there were another 21 men in his village and none of them knew that he Adam was going to be the one whose whose genes would persist that his surname was going to assist and he himself had no idea that that was true but certainly everybody called spaghetti in the present generation is his descendant everybody called spaghetti in the present generation has his Y chromosome which passes down the male line and in fact everybody in the present generation not only has his Y chromosome but both men and women in that village have got lots of his other genes too because his genes persisted whereas others other individuals genes were less successful so in other words this this what this village is inbred okay and the next village is also inbred managing relatives but just by chance a man with a different name took over there so each of these village is smaller than isolated or much less sexual than there might actually be they're marrying relatives you're all descent Marie de ser descendant of the famous Adam of course inbreeding the marriage of relatives used to be very common even in our own noble royal house there were plenty of there were plenty of cousin marriages Queen Victoria married her cousin Charles dog Charles Darwin was very concerned about cousin marriage because he himself had married his cousin and he actually wrote to Gorton asking whether this was going to cause any problems and got thought it might Darwin being being a genius which he invented she certainly was then went on to study the problem and it's his likely off the point but it shows what the power of what Darwin did he was interested in the effects of cousin marriage on human populations on human families what did he do he went look worked on flowers and only with the theory of evolution that had become possibly even to contemplate that work on flowers would be relevant to work on humans but no we did that a couple of Rouladen digestible books on self and cross fertilization in plants in which he suggested that self fertilization which is in plants which is simultaneously male and females what Woody Allen used to call sex for somebody you really love yourself okay self-fertilization he thought was generally a bad thing so he got very worried about the effects on health in some senses the same is true as you'll see for a very close inbreeding in humans sometimes the embedding in humans goes to an extreme Queen Victoria was pretty was pretty taken she had a nine children and many of them married their cousins if you were to draw a pedigree view of the other of the modern royal family you would find that many members of European royal families traced descent from Victoria she became known as the grandmother of Europe and every single member of every European royal families traces traces descent from somebody called John frieszo who was I think a Swede who lived in the 18th century so they're reasonably inbred ok but this has nothing compared to what used to happen a few hundred years ago here are the Bourbons the famously eccentric and mad Bourbons and these are the numbers of ancestors that they had different times in the past as I said if they're if the Bourbons had been a purely sexual out breeding population two four eight sixteen thirty-two at seven generations they should have had each one of them one hundred and twenty eight ancestors well you'll see that Alfonso the 12th the king of Spain instead of having 128 ancestors seven generations back only had eight and that's pretty impressive okay interestingly enough he married Victoria Victoria's granddaughter whose name was also Victoria and she Victoria's granddaughter brought the blood disease haemophilia into the Spanish royal family so that really didn't work out particularly well but it was a huge amount of inbreeding and you find that if you go further back into these ancestry if you draw the pedigree of an inbred family the signature of inbreeding or asexual or less than sexual reproduction is to find loops in the pedigree and here's the pedigree different different horizontal lines of different generations the vertical lines are lines of descent and you can see the loop after after loop and that means that this merit this this mating was actually pretty damn I'm pretty damn them inbred do you go further back again you find the things go even more extreme Tutankhamun's body was done was DNA was looked at not long ago it turned out that it was very clear that he'd had sex with his sister because she his sister had been killed after he died she was pregnant and the children could only have been to the two of them's offspring he himself was almost certainly the offspring of a brother-sister mating and this comes from the belief which the Egyptian pharaohs had and no other British royal family has in mitigated form that they are actually the bloodline of a god okay the the the to deny moon thought that they were gods and if your God he's on some non blue blood getting in there but if you look at to tangu moons get skeleton he had real problems he had severe skeletal deformity and he would have numerous walking sticks and so on were found in were found in his in his in his grave so we can we might deplore this fact but there's no doubt that close inbreeding causes lots and lots of problems on this Darwin himself found that Darwin was a keen was very keen on dogs okay yeah the dog of his own he'd wrote some he wrote a wonderful book called the expression of the emotions in man than other animals which was incidentally the first ever book to have photographs in it not many people know that in wish he showed pictures of people's faces when they were frightened or happy or sad also pictures of dogs faces when they were growling or or terrifying and showed parallels between them but don't was very keen on dogs and he was particularly keen on Bulldogs he had a bulldog of his own and I'm not a great living as I do in Camden Town I'm not a great dog lover and I'm going to show you for obvious reasons but that's a picture of the bulldog at 1817 and the Bulldog was bred for a particular purpose which was football baiting okay very cruel that's what it was there and to be fierce which it certainly is it had to be able to leap up which it has strong muscley legs and attach itself to the balls face often and hold on okay that's why it has this undershot jaw so you can grab onto the bull's nose and hold on not be shaken off by this boy terrifying ball well got it was a handsome looking animal in 1817 people breed Bulldogs and dog breeders then and low behaved in the most outrageously irresponsible fashion because they frequently not only make brothers and sisters together in order to get to get the OP the allegedly optimal offspring but a very common pattern is for a very successful male dog to be mated to his daughters his granddaughter's his great granddaughters over several generations in the hope of getting that prize at Crufts this is the animal which won the prize of crufts in 2008 and that really isn't tragedy you may there was a programme just after that on the way you see some of us scene which I made a small party called pedigree dogs exposed weak led to a huge row that could that BBC would no longer cover crafts but that's what happens if you in breed ok to an extreme extent now what so we therefore we really need to know how in breed how inbred we each are and how what effects that has if you begin to work out the possible and relatedness of each one of us I can actually illustrate how likely to we are to be inbred by asking you to shake hands with the person next to you if you can stand it okay feel free to do so and I adjust with a 50% probability I have just introduced you to your sixth cousin okay and that's the average degree of relatedness to get back to us to bring it back to a sixth cousin who might have lived in the time of Darwin you to get back to a probable sixth cousin with a 50% chance of accuracy you only have to go back to about Darwin's day if you to go back to the to the to the to the time of megiddo about 3,000 years in fact it turns out that everybody in the world from Papua New Guinea to Australia to China to North America to Africa is descended from one individual well who lived about 3,000 years ago we don't know who that was of course you don't know where they were but they are we're all descended from that individual so we are all descended from more closely in bed than we actually think so what effect does that have on human health how can we in personal how can we measure it and secondly what what effects might it have on health well clearly you most people unless you happen to be either divine or a god most people don't keep petting detailed pedigrees so you don't know how to do it but actually Darwin then have another good idea sure how clever he was he and his son George Darwin were interested in the effects of inbreeding of just in flowers but on humans and George Darwin and clever notion he wrote to the the colleges of Oxford in Cambridge and he asked them how many cousins they were in their colleges how many people in the college cousins and of course in those eras the classic and explosive days no longer true needless to say in Austen Cambridge I'm at least are plenty of them were cousins because they came from a Socratic families who tend to marry their relatives and then here then he asked the members of the boat race crews of each college or whether they were cousins or not and it turned out that if you were in the in the college boat you were less likely to be a cousin in other words the offspring of a although closely in bed by then if you were just some nerd or until lightly every day and we're not at all athletic so that was some hint not a very scientific int that cousin marriage was bad for you it was a phony ruined by the fact that actually st. John's College Cambridge cheating and give told him completely false figures and when you took that out the whole thing fell apart so that didn't work that didn't work but then Darwin had another typically brilliant idea he realized as had gotten that are quite a good way of measuring measuring cousin Mary measured relatedness is to ask how often how many names are there in a particular population in the racial relation to the number of people okay and that's very clever because this is the Italian hill village story on a large scale and it's obvious when you think about it if you go to somewhere like oh so which is a pretty homogeneous population you'll find that in the phonebook that are on the average something like 80 copies of every name on the average over the over the population if you go to New York there are which is a fantastically outbred population there are on the average two repeats of every name which means there are plenty of names is just there once and of course our New York is a much more outbred population a much more mixed population than our populations of Scandinavia so this is a process look at names and it turns out there's a whole new science really of name of booking of names and it's even more powerful method of doing it which is called a sauna me having the same name and you study that you go to the marriage records of places like Finland or Croatia or mini Catholic countries and you ask how often two people with the same surname get married now that doesn't work very well in sort of Kabir names like germs because the name Jones has originated hundreds of times just means solid John but it's better with the name like Attenborough should we say if you're both called Attenborough it's quite likely that you're both descended from an Attenborough who live not that long ago and and hence although you might not know it you might actually be relative might be relatively and you might be relatively closely related and the figures on names are quite remarkable on the average time depth of a Welsh name most Welsh names came into being only about 300 years ago when the English invaders insisted we stopped at the old system where you call yourself after your father your grandfather like so that everybody was the son of John became a Jones everybody others who are the son of John became Elevens because there's no J and we also - even Evans others of his sons at John became a Jenkins John's kin so you know not many games in Wales England has a time depth of 700 years Japan only 150 years because they only came in hundred fifty years ago and China the average time depth is 5,000 years okay and you can see the power of inbreeding because the depth time depth the longer you go back the more likely you are to find patterns of shared relatedness and in China a fifth of the population which means about 300 million people share three family names in Britain the average numbers of carriers of a particular surname is 17 okay in France the is 28 in France it's so it's in transit 17 an island 63 and in China at 75,000 okay and that's because the further back you go with these ancients earnings the more likely you are to converge on a shared ancestor now it turns out that actually this science of I Sanne me is overlapping with the science of genetics because what we can now do of course is to ask about descent using DNA and we can particularly asked about descent using the Y chromosome the Y chromosome the male chromosome passed from father to son to grandson just like the Western system of surnames has been read from end to end and there's a whole industry of which we have some of my colleagues are involved in of looking at individual differences in patterns of white chromosome diversity from place to place and a few years ago somebody had the bright idea of saying okay well names and wine chromosomes and pretty much the same why don't we write to people with particular name surnames and look at their Y chromosomes and who is the obvious people to look at the obvious people to look at with the Aten Bruce okay so David gave some and Sun because in Australia gave some very saw the Latin Burroughs wrote in and they compared them with a bunch of plebs known as the Smiths okay and the Smiths of course the name Smith just means a work in iron and that's the reason again then again and this is these are family trees of the Y chromosomes of the Smiths okay and you can make kind of a you make the family tree by asking how similar different Y's are and asking how many arrows how many changes that would have to be from one to the next and you can see on in the top B they're the Smiths there are five hundred and sixty thousand Smith's in Britain and they're a highly bastardized lot okay there are some groups of rather similar Smiths but they're not particularly homogeneous look at the admira's account in contrast that are 932 Attenborough's in Britain and you can see that almost every almost all of them share the same Y chromosome so they almost all descend from one individual called Adam bruh who probably lived in the Middle Ages near the fort at Enberg possibly any possibly in the English Midlands okay so the Attenborough's show that surnames actually tell you a lot about genuine patterns of genetic relatedness and you can draw a map of surname diversity for example in britain and i'll come back this in the end the warm of the color the more names in relation to population size okay now this was telling you see how I put extinct centric reasons they waited it by population size which is wrong annoying but you'll see that Wales is pretty cool okay there aren't many names there partly because they knew somewhere like Cambridge and Oxford are relatively inbred in more than one sense of the word London is enormously diverse and is becoming more so Scotland is fairly inbred um if you look right at the top of the map there you'll see the Oakland A's and the Chevron's and you'll see there's a that there are really very few surnames in those places not come back to them at the end of the talk so the surname story does actually can tell you something quite interesting about about patterns of relatedness so what are the patterns of relatedness and marriage across not just in Britain but across the globe well in fact it's actually really pretty common you can draw a map or what's called consanguinity the incidence of marriages closer than second cousins many of these marriages are cousin marriages some of them are even closer than cousin marriage is a very common pattern in southern India and parts of the Arab world is uncle niece marriage and that's closer genetically you marry your brother's daughter it's really quite common and you'll see that the bride's have red the color the higher the extent of consanguinity consanguinity and in some places such as bits of parts of Pakistan and in their legs up Saudi Arabia more than half of all marriages of this kind and indeed in Saudi at Saudi Arabia the overall pattern of relatedness of two average two Saudis taken at random is of equivalent to being first cousins once removed in other words they're equivalent to being related as they are to their parents cousins and that's pretty damn close okay and it has with our question some kind of some kinds of effects we're all here okay some without question has health effects now the place where you can see those effects most strikingly is are strangely enough in an unexpected part of world which is Finland and Finland which now is an affluent country with an excellent health system socially very stable for many years was on the edge of the known globe genetically the Finns are not like other Scandinavians they're much more like Siberians they came across the northern part of Russia and Finland has 33 inherited genetic diseases which have found nowhere else in the world okay and they're what we call recessives in order to show the effects you need to copy to the damaged gene and the finland has become a natural genetic laboratory and here's a young girl here who certain unfortunate certainly dead now I took the photograph by 10 years ago bit more now with a disease that's called variant late into infantile neural deprived Lippo Fosco doses and it's not going to be in the exam a students always panic which is a nervous degenerative disease a bit like tay-sachs disease but nothing can be done about it the nervous system basically poisons itself and children die as an early aging there's a dad there she is and if you look at the map on the left there VL incl you can see it's concentrated in one part of Finland that's called Ostrobothnia okay now in the old days and to some extent still today Finland consisted of a few islands of people surrounded by a sea of trees people lived in tiny isolated villages where they never moved away and Finland had extremely good family records through the Ruth Lutheran Church and here are the pedigrees of some of those cases of VL incl and and here's at the bottom there the what were the horizontal lines the generations the verticals are from one generation to the next circles of female squares and males and black tin means that you've got the disease and the bottom on the right there the young lady who's blacked in she has the disease okay which means her parents and so her dad must have carried one copy each and you could find other examples and it turns out Neal nearly all the examples descent from one man who lived in about 1650 and he must have carried a single copy of the gene and if you look you'll see there are several loops in that pedigree because people didn't close together and finally those two copies which had come down the generations inevitably came together in that unfortunate young girl and that's somebody else in the same generation in a we have another case where we can't link it to that man but that's simply because the information isn't there I'm sure if we had the information we'd link it to that chap there so that's what inbreeding does it certainly does increase the amount of them of old specific genetic disease but it does more than that because if you can you can ask the question there are some more inbreeding leaves there ingredient plenty video embryo loops in Finland you can ask a wider question even if you haven't got the pedigrees which generally we don't have in human families you can simply ask people you know are you are you related to a person you might are you lost me because my and the answer is the effect is not small here's the patterns of childhood mortality and morbidity in the ER in the general British population North European population and in British Pakistanis in particular population of Brantford which consists of a highly inbred population largely because there's strong social pressure less now with 70 10 years ago there was strong social pressure on young people in Bradford to marry a cousin in Pakistan will then come join the family okay and you can see that for congenital malformation like cleft lip for disability is different kinds from genetic disease early death there's about a doubling in overall genetic damage in these inbred populations compared to outbred populations so people have got really more and more interested in in what M breeding can do and we're beginning to find some really quite striking effects of inbreeding which is begin of the cause a certain amount of let's miss that bit out okay how can we measure it okay what we can do is we can treat DNA as if it's a surname now Y chromosomes are surnames because they don't reach awful and breakup every generation now we all know that what sex does is to break up and BRE shuffle the genetic cards each generation certainly if the genes are interested in our own different chromosomes they will rearrange automatically at random when each sperm or egg is made but if the genes involved are on the same chromosome and a long way apart the chromosome itself will break up and you'll have this rearrangement but if you look over short lengths of DNA and by that I mean some millions of DNA bases this breaking up process will happen only very rarely so for much of the time blocks of DNA will be passed down the generations okay without being reshuffled know I talked about this I Sanne me game marrying somebody with the same name and here we have a marriage of two Attenborough's okay we've got their 10 letter ordered his name they both got the same name you can line the two names up together and there's a perfect match they must descend from the same individual but you can do the same with DNA yes at the bottom we have ten or so lengths of DNA we should take them from somebody at random and it turns out for this individual he or she has got exactly the same copies of all the genetic sequence along those ten letters but we're talking about ten letters we're talking about a million letters now just to use that just to use the just to use the technical language this is called a run of homozygosity roh which doesn't mean Royal Opera House to jet assists it means Ramadan zygosity and what you could do is to go into populations easily the technology that we got today and you can get some people and grind them up or but there are other way get them to spit into a tube and simply ask how often do you find great copies numbers of copies of great if the incidence have doubled up copies of DNA of particular lengths okay and this will tell you with some accuracy how inbred how much inbreeding there has been in that population over time well the work was first on five six years ago now and somewhere at first sight up science agree at surprising in Croatia okay and oddly enough I did my PhD the dawn of time in Croatia as I often say I'm one of the world's top six experts in the genetics of snares on the other five agree and I did the snails of Croatia I had a lot of fun at oh that's another story without realizing there was a much more interesting human story just just waiting to be told and now it's been told well these islands are like many places in the Balkans are very resistant to people coming in they're very closed communities and they've got very very good family records well I'll talk you through this rather complicated slide let's just look at the right where it says more than 10 okay that more than 10 means the proportion of the population that has doubled up copies of DNA same sequence same genetic surname more than 10 million DNA bases law and that's pretty that's pretty long okay and let's look at the right hand of more than 10 segments the endogamous Dalmatian that means Dalmatians people on the islands who married somebody else from the islands something like 30 percent of the population has got a doubled up segment of the if you look at mixed dalmatian that's the blue one number three or so it's much less interestingly enough if you look at the second one the pink one they're in dogmas or KD ins and all KD ins of people who come from Oakland and much so ever it is surprised it turns out the population of Orkney is almost as inbred as the population of these remote islands and they also have very few surnames then if you move to Europe as a whole or Scotland or England and there's very few people with these huge numbers of doubled up copies of DNA so now what we can do we can actually in Croatia that actually fits very well the figures you get from those from those experiments fit almost precisely the figures that come from the marriage records issue other reasons why they chose it but what we can do now is measure the level of inbreeding in any population or any individual with an automated test would take us that take you a morning okay simply ask with a chip how many runs of homozygosity have you got we will tell you how inbreeding you are how then bread you are and it turns out there naturally it can have really severe effects here's a case of extreme inbreeding this is the child of incest brother-sister mating and the black tin green sections are runs of homozygosity okay and they're huge they're hundreds of billions da bases long okay and that's not surprising because he his parents were were brothers and sisters and this child is very severely compromised and lives in a children's home will never never managed to make a living never managed to live in the real world it's got severe mental disorder but that's an extreme case and we know from the dysfunctional family that he has the problem but what can you do you can go into various kinds of disease and you can ask what's the incidence of runs at home at homozygosity in people with the disease versus people without the disease and this is a this is a colon cancer and at the top come vs. controls people without colon cancer at the bottom and I think you'll see that the proportion of people with at large numbers of them runs upon what homozygosity black blobs in the cancer patients is much higher than that in the general population and that's true of a number of the conditions this is schizophrenia let's probably a bit too complicated that one this one early onset Parkinson's disease just the same as you if the morons are homozygous that you've got the more likely you are to get Parker's disease there's even an increase in infection rate infection rates with homozygosity so I'd really tell that we that really tells you that this inbreeding pattern is really important and it's now an important is becoming will become this is all very new last year or so will become a standard diagnostic tool in many conditions I'm sure so let me end up by asking well what's the future what so when we get to Armageddon what we're going to look like well the answer is really that we're going to look quite different because of this wonderful eugenic tool known as a seven four seven okay because no longer do we behave like the fins the fins now come to use the L view and find themselves a mate from China that by no means unknown and people are no longer marrying the boy or the girl next door because they've got no choice you can see that in America if you look at DNA samples including preserved DNA samples over people born in 1900 versus those born in 2000 you'll see a dramatic decrease in the incidence of runs of homozygosity so we're getting more and more out bred but you don't need technology you can do it with surnames here is my family name the Joneses okay a Welsh name and in 1881 one in 1881 as you will see we were combined safely confined behind the electric fence on offers dike and we were all in we were all in West Wales okay by 1998 the Joneses were on the march okay you have to make a 1 percent of the population to get on to this map we haven't we've got two oxen we haven't got to Cambridge but we are also in London actually and that's happening everyone you can see that everywhere people are absolutely on the move so I think really what we're facing what we're seeing is a new era of human evolution which is triumph of the mongrels as incest disappears that as a result we will have no choice but to take up folk dancing and we'll stop there thanks very much Steve for a fascinating lecture we do have about 10 minutes I think for questions and let me begin the pattern that you've just described could could it possibly explain the supposed increase in human intelligence it's been suggested that it's possible I mean trouble is if try to it's frightfully easy to make ad hoc hypothesis by hearing evolution it has been suggested it's also been suggested that it's it's responsive as possible for improvements in human height and all this kind of stuff and then maybe some truth in it but it's great rather difficult to test what's much more important in both height and intelligence of course is the environment tend to forget and the fact that this certainly gene genetic variation behind human human height diversity and here on IQ de this is no question that's true no we haven't found the genes and that doesn't alter the fact that that the environment is involved you know the classic case here's the difference in height between the people between people of North Korea and South Korea which is five inches now and then actually these people are the same for the people in North Korea starving the people in South Korea eating well yeah so um it could be true that I'm not convinced in much evidence in please any other questions is it going to be in the exam yes I need a microphone you thank you so I come from Bangladesh so up until very recently in fact even now people living in very limited mobility very close sort of you none probably very in bread you're freaked me out about the Finns but would it be ideal for me to have offspring with a Finnish guy what the pros and cons of that yeah if you've been to Finland you might think twice in Finland amazingly enough has the highest murder rate in Europe it's hard to believe they fight with knives when they're drunk but um well I thought actually is there is not a none serious question I mean to oversimplify the issue I think taking the example of the common the common a single gene genetic disorder in European populations which is a as most of us know though you did the disease cystic fibrosis okay which is a very nasty condition which can be controlled but you know you don't you don't want to have in the city called Curie okay and to have it you have to have two copies so you sometimes and it certainly happens you gets a woman shall we say from a family in which there is a history of cystic fibrosis who is very concerned about it wants to be sure that she isn't going to have a child with cystic fibrosis what's the best advice you could give up Marie of Nigeria because there's no cystic fibrosis in Nigeria so her kids are bound to be okay in Nigeria with sickle-cell disease which most of us have heard of which is a bit the same the advice to a Nigerian is marry somebody for a brisk with because there's no sickle-cell disease in a resident so in that sense I think there's a case to be made but only enough Biddle's the guide John Beatles who did much of that consanguinity stuff he spent a long time asking the question with huge datasets okay let's ask what's the relative health in India actually only Pakistan of the children of cousin marriages versus smokers pages and he was baffled to find that the children of cousin marriages were better off and healthier than the children non-customers it just doesn't fit okay but then and these are very capable bloke and then in collaborate and so he looked more deeply into it and it turned out was entirely due to social pressures because you marry a cousin if you have some wealth in the family and you want to bring the dowry in to keep it in the family and if you've got wealth in the family your kids are going to be better treated if you're an untouchable you've got no wealth nobody cares when you marry so on your poor and your kids are in poor condition so I say with some passion actually that Jim for most people genetics is the great irrelevance I would have followed you I would depend on the healing power of lust that isn't always true I mean there are particular families for example Ashkenazi Jewish families in North London where there's a high incidence of particular nervous disease where this really is an issue and actually people are careful about their managed patterns and have succeeded in really ensuring that none of the kids with this disease are born so you for some people it's important but the most people since just irrelevant while the backgrounds coming up should include of course that the other good example apart from the British royal family if cousin marriage is the Rothschilds and the absolutely big Jewish banking families of the 19th century so I got some reasons you were for five generations every must you are my disciple okay I'm now again was overtly or covertly an attempt to keep the money in the family there's an option option I'll stop rambling in a second away you can measure the effect is to ask is to measure what's called the marriage distance how far apart was the birth price of yourself and your partner versus that of your mother and your father your mother's mother and your mother's father and so on and generally speaking you'll find an enormous increase over the recent years myself and my wife were bought 3,000 miles apart because she was born in New York and was more than West Wales my parents were three miles apart and one very rude student muttered one year and it shows your comments are more interesting my question and does this mean that the rare genetic disorders will eventually disappear all together no what it means is that in time this is already happening the rare genetic disorders in Finland shall we say they will go away for a time as finns no longer married by the girl next to all they go to america summoned many of doing they travel they will go away in the next generation maybe the next generation but the iron logic of genetics tells us when we get back to some kind of global new equilibrium they will come back again the genes haven't gone the genes themselves haven't got away in time they will come back and be meat but by then we all tried in a nuclear armageddon anyway so it doesn't matter yes sir at what time in the past in the during the development of man was the brain large enough to be progressive which distinguishes us as life-forms from every other life form on earth well people people argue about that and the brain got pretty big with Homo erectus which we're talking about four million years ago or so okay it was pretty big then the interesting thing is that one day and if you go back to places people like Australia Australopithecus Lucy our brain was small okay and we don't quite know why the human brain got began to get big many people would say has to do with standing up but once you stand up you're giving again the horizon you can travel further in that concept for this speculative but what's interesting is that the human brain the modern brain Homo sapiens the species to which many of us claim to belong possible laughter it hasn't got any bigger since the days of we appeared when we first appeared on earth [ __ ] anything's got something slightly smaller certainly smaller than that's only because the Neanderthals were big and clumsy inaudible okay so I have the it's about the same size of the chrome manual very modern human brain now I have the dubious privilege as I mentioned of living in Camden Town and if a crow man young man would come and sit next to be on the tube probably wouldn't notice he might be covered in skins and grunting but this is Camden Town okay so then so they're physically and MIT in terms of brain size included he has no eye we have not changed compared to him but mentally we have changed entirely so I think that human evolution is overwhelmingly being in the functioning of the band rather than the structure of the brain so I will suggest that insofar as you can define what progress means I think it probably began with the human species apologies if I misunderstood what you said but I think you said that the whole of humankind could be traced back to an ancestor from Armageddon which is only a matter of a few thousand years ago I was confused by that and during that time scale so isolated communities already develop around the world well so how does that that calculation I mean it's a fairly recent paper which is lots of hand waving in it okay it debate depends on the amount of migration the length of generations the relative success of males and females and very often males are far fewer males mate than females mate because some males have many mates the sizes of populations so there's an awful at the rate of mutation pretend that's that they use the rater mutation to try and work out the timing so it's full of guesswork but you do quite quickly get back to that date of about 3,000 BC for the universal and what the ancestor of everybody the universal ancestor almost every Britain probably lived in about 1066 and you only need one person to you know but on a classic case are there's a family in Yorkshire called the Rivers's and the Rivers's are named after Revo a B so it's a fine york should name not bloody foreigners here in baton okay so if you look at the rebus ease it turns out they got an african y-chromosome why is that because at some time five hundred years ago was by no means uncommon an african probably not a slave actually probably some kind of representative or merchant came to our britain married into the Revis family his genes of some sense has been diluted away but by virtue of his to his coming here and getting into the population of Yorkshire five hundred years ago it's quite likely the tens of thousands of people in Yorkshire haven't have a shared ancestor risen and lived in Africa five hundred years ago so you have to go back all that far but that is this is what guesswork it's kind of embarrassing that you know as you know Archbishop Ussher gives the dates of Adam and Eve to be 4004 BC October the fourth 10:30 in the morning it was the Thursday and it's kind of embarrassing for us atheists to realize that genetics kinds of agrees with them I think that's a good moment to stop thank you very much indeed see for a really fascinating lecture for honoring us with your presence here this evening you

Channel: Gresham College

Views: 47,221

Rating: 4.7716703 out of 5

Keywords: Zoology, Biology, Science, Genetics, DNA, Sex, Reproduction, Evolution, Genes, Family, Incest, Anthropolgy, Humanity

Id: bugu_9b0bTU

Length: 67min 12sec (4032 seconds)

Published: Thu Jan 31 2013