ABOUT THIS EPISODE

Our understanding of heredity and genetics is improving at blinding speed. It was only in the year 2000 that scientists obtained the first rough map of the human genome: 3 billion base pairs of DNA with about 20,000 functional genes. Today, you can send a bit of your DNA to companies such as 23andMe and get a report on your personal genome (ancestry, health risks) for about $200. Technologies like CRISPR are allowing scientists to edit genes, not just map them. Science writer Carl Zimmer has been following these advances for years, and has recently written a comprehensive book about heredity: She Has Her Mother's Laugh: The Powers, Perversions, and Potential of Heredity. We talk about how our understanding of heredity has changed over the years, how there is much more to inheritance than simply listing all the information we pass down in our DNA, and what the future might hold in a world where genetic manipulation becomes widespread. [smart_track_player url="http://traffic.libsyn.com/seancarroll/carl-zimmer.mp3" social_gplus="false" social_linkedin="true" social_email="true" hashtag="mindscapepodcast" ] Carl Zimmer is a leading science writer whose work regularly appears in The New York Times, National Geographic, The Atlantic, and elsewhere. He is the author of thirteen books, including a university-level textbook on evolutionary biology. He has been awarded prizes and fellowships by the National Academy of Science, the American Association for the Advancement of Science, and the Guggenheim Foundation, among others. He teaches as an adjunct professor at Yale University. Download Episode
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TRANSCRIPT

00:00:00hello everyone and welcome to the mines K. podcast I'm your host John Carroll and today we're gonna be talking about heredity this is of course a very old idea the idea that there's something inside us some properties some features that get passed down through the generations so we
00:00:18inherited something from our ancestors and we send something down to our descendants back in the day there used to be the thought that royal blood was handed down that the right to be the king or the queen or the emperor depended on who your parents were I suppose
00:00:33there there's still countries in which that is the case but we know a lot more about how heredity really works now than we used to we know that all of our cells have a little molecule in them called DNA and that DNA is a little code it's a
00:00:47chain of letters AG C. T. that the arrangement of those letters tells us what makes up who we are or at least there's a simplistic version of it where you think of DNA is kind of like a blueprint that if you knew what the DNA was you could
00:01:02predict exactly what the organism was going to be maybe even you know what kind of food they would like or what kind of occupation they would have later in life today we know it's a little bit more complicated than that there's more going on than just our DNA
00:01:16to make up who we are and not only nature versus nurture but even the nature part is very complicated there's epigenetics and development factors there's mitochondrial DNA there's the expression of different parts of the genes that we have and so we're in a very very rapid state of
00:01:34evolution as it were in terms of how we think about how heredity works these days you can get your genome sequence to consented to a company pay some money and they'll tell you something about your genetic heritage on the horizon we see the ability to edit jeans we
00:01:52can do it in some ways now and the ability to do that for human beings probably is not very far away so it's natural to mention you know can we design with the next generation of human beings is going to be like we design the animals and plants
00:02:06that make up the rest of our ecosystem these are important questions as well as fascinating ones so we have %HESITATION today Carl's immer as are against Carlos one of the very best science writers working out there he's been working and writing about this area of genetics and heredity
00:02:22Indian a for a very long time you may know Carl through his blogging on his Twitter account his New York times column where you may have heard him on NPR now Carl has a major new book out called she has her mother's laugh the powers perversions and potential
00:02:39of heredity it's a door stopper it's a big one %HESITATION but it's full of fascinating individual human stories as well as the deep science behind what we know about heredity so we're gonna talk about how we're ready works what we do and don't know about it and most
00:02:54importantly where the new knowledge the regaining every day might take us it seems very plausible that what we're learning these days might dramatically change how we think about being human beings so let's go Carl Zimmer welcome to the mines K. podcast it's great to talk to you so
00:03:30no we've known each other virtually this online you know since the early Halcion salad days of the blogging world right it didn't %HESITATION is that how you got to know you reading your blog and you read mine absolutely yeah back when blogs were the future blog yes and
00:03:45now we're in the future and no one writes blogs anymore they delivered us here exactly the future is a is a journey you know that's and we've we've been to the future now in the post future so I couldn't help you were you written this gigantic magisterial book
00:04:00about heredity inheritance she has her mother's last and the subtitle of course the power provisions and potential of heredity and while reading it I can't help but think as a physicist you know my goodness how lucky I am that what I do for a living doesn't really matter
00:04:17to people's lives there's a kind of science that everyone has feelings about right to you does that come through in your work %HESITATION I I think that everybody %HESITATION clings to her ready and a profound way and I see that when I give talks about my book I
00:04:36mean I have learned to keep my prepared remarks fairly short because people just have tons of questions and and the questions come from the fact that we use heredity did define who we are and also what is our connection both to the past into the future I mean
00:04:55you can't ask for anything more intimate than that yeah and so the future in terms of our %HESITATION children are descendants you mean sure absolutely and and also like what if we tamper with her at the %HESITATION of other species and you know then what what is what
00:05:12is left after we're gone well you know heredity will carrying on those are two changes into the future so I think you know everyone who is involved in this conversation right now %HESITATION knows a little bit right you know we're not entering in we're not telling people something
00:05:29they've never heard before that there's something called DNA in our cells and carries some information so let's try to remember what it was like before we knew that right people still had an idea of inheritance and heredity and things being passed down through the blood even before Darwin
00:05:45and Mendel came along right I mean it's kind of hard to reconstruct the way people fought in the past especially when they didn't use the concepts and the words that we use today and yet you know we can we can start to get some clues about about it
00:06:03just by looking back and and trying to piece together you know for example %HESITATION yet there where ideas about blood as you say you know we we sent still use the word blood to to talk about you know what we really mean by jeans you know there's the
00:06:22blue blood for example in I like blue blood is something that is like well you come from a blue blood family in other words somehow like that is inherited down through the generations %HESITATION you're sort of status I mean the irony is of course that the phrase actually
00:06:36comes from a particular time in a particular place it was in Spain in the fifteen hundreds when %HESITATION in Spain were trying to distinguish themselves from Jews and Muslims so so they this is where and this is where the whole issue of race comes from I mean literally
00:06:56the word race starts to be used in Spain %HESITATION in this way and so you know they're talking what what what's entries at fifteen hundreds %HESITATION fourteen hundred and into fifteen hundreds and I the so the idea of blue blood was that if you were you know racially
00:07:15Q. R. than someone could see your veins through your translucent skin and so you know you can kind of get these ideas about how in western society there were these ways in which we started to define ourselves as as being sort of made up of something that was
00:07:37being passed down through the generations but you know it really but you know and then it wasn't until the eighteen hundreds that people like Charles Darwin actually like framed it as a scientific question like okay there's something something molecular that is being passed down through the generations and
00:07:58explains why people have these traits that seem to run in families so what is it Intel's yeah I mean Darwin would have said the word molecular right but it but we know what you mean there is something that is being given from parents to children what did but
00:08:16without jeans without DNA or anything like that %HESITATION with this basic idea that we inherited from our mothers and our fathers did anyone ever wonder about the fact that why are we always just exactly halfway in between our mothers and our fathers in every trait they're they're clearly
00:08:31seem to be variations around that the people in the mental Indian a worry about this fact yeah they I mean they could see for themselves that %HESITATION these patterns are already we're not simple they've they really puzzled over them mental was just in a long line of people
00:08:52who are scratching their heads and you know these were plant breeders these were animal breeders %HESITATION in the seventeen hundreds %HESITATION someone named bake well in England the legendary because he created a new breed of sheep are any did it by a carefully breeding different kinds of sheep
00:09:12together %HESITATION and and coming up with these %HESITATION rules of his own for how how to breed them and it was a incredible accomplishment you know because you know people would breed animals and you know like their offspring would be all sort of a mess they would be
00:09:28like right now all this variation when you know if you're breeding animals you all you want them all to be the same you know if you want a particular kind of meat from an animal you want them all to have that same tasty wanna kinda will want the
00:09:40same all %HESITATION so it was a huge puzzle and struggle and and the stakes are enormous I mean you know by the seventeen hundreds and eighteen hundreds entries were actually looking at breeding in other words heredity as part of their national wealth you know if you could breed
00:10:00new crops and you live stock you were going to make your country rich I love the practicality of it it's a reminds me of you know how thermodynamics which can be very abstract and theoretical subject arose from trying to get better steam engines right as you know this
00:10:16this is definitely an area where there's a give and take between people with boots on the ground trying to make better products and trying to understand the world better as as scientists yeah it is interesting that I mean because you know we assume that everybody must have thought
00:10:32about her ready we the way we do and wondered about it the way we do five hundred years ago or a thousand years ago but they just didn't and it wasn't really until that some practical questions %HESITATION drove the really think carefully about this and you know the
00:10:52other people in addition to breeders where psychiatrists in the early eighteen hundreds particularly and France and also to some extent the United States and elsewhere psychiatrists were trying to understand madness and then they were truck by the fact that when they would do questionnaires for their patients their
00:11:17patients often had people in their family or more distant relatives who also were institutionalized or you know maybe they are had you something that seems like a form of madness and so they said so so is this a hereditary disease and and if so how on earth could
00:11:37this be passed down through the generations and dark Darwin actually read a lot of psychiatry when he was developing his own ideas %HESITATION heredity so this connection between heredity and intelligence and madness and thought was there from the very very beginning yeah a lot of the things that
00:11:56we're talking about right now people were talking about a hundred fifty or two hundred years ago with just as much loudness and passion and conflict maybe that just as much because now we have Twitter and they didn't have that they're so that's an amplifier that they didn't have
00:12:14yeah but they had pamphlets you know like him they did you know that you have a lot of the stuff would would get circulated and things like pamphlets where you know you you get a new pamphlet every day like I I I I I feel like Twitter is
00:12:27just an extension of the old traditions of pamphlets so maybe blogging is the past more than the future I don't know where podcasting fits in them so then do we did get to genetics right to real genetics to %HESITATION mental mental by the way I have to always
00:12:43say this %HESITATION %HESITATION I went to an Augustinian University Villanova and Augustinians have a slight inferiority complex compared to the Jesuits who are wonderfully intellectually you have this wonderful intellectual tradition but we have to really important Augustinians in history one was Gregor Mendel and the other was %HESITATION
00:13:03Martin Luther so they weren't always you know that the best Catholics but did they did they did affect the world in important ways so mental among other things he helped sort of pinpoint this discreet in this right of heredity that there could be like you get this feature
00:13:20or you don't so there must be somehow it wasn't just a blending of your two parents there is some piece of information a quantum of his as we call it is being handed down through the generations right mental then call them jeans %HESITATION sometimes the terms of use
00:13:37get translated as factors so there would be some kind of factor that was in a plant and there was an almost mathematical beauty to how these factors combined in new offspring and then produced a trait so just want you know an example that people may recall from high
00:13:57school is that peas can be wrinkled or they can be so %HESITATION and if you cross too wrinkled plans together there you're gonna get nothing but wrinkle peas if you cross two smoothies together %HESITATION you might get nothing but smooth peas and then the next generation after that's
00:14:18with peas and space bees forever on the other hand if you Ross as smooth pianist move together you might be surprised to suddenly have a quarter of the peas being recalled %HESITATION and %HESITATION and so the fact is that %HESITATION these in that wrinkled factor can hide because
00:14:39it's what we would now call well great actually medical to recessive so %HESITATION yeah so so that was the first recognition that that there was a service there's a server thinking about heredity and we need to kind of distinct the parts DD invisible factors they get carried on
00:15:02through the generations and then sort of what you see that right what scientists call the phenotype then we started finally figuring it out we're moving quickly the history here so when I get to the modern world but it wasn't old twentieth century that we were able to identify
00:15:17these jeans as being carried by this wonderful molecule the DNA and %HESITATION Watson and Crick at center and by that time correct me if I'm wrong but there was already this new synthesis of %HESITATION genetics and evolutionary biology natural selection Darwin and so the DNA was just sort
00:15:39of figuring out not just but was figuring out what the mechanism of that was yeah well that's a beautiful distillation of thank eighty years of really arrive science yes exactly yeah %HESITATION you know it is the people I've known about DNA realizes since the eighteen hundreds but they
00:15:59were kinda like how what is this weird stuff and %HESITATION so as to make just make that very clear they knew that there was a molecule called DNA exactly if you if you pull the part cells you would find different components so you find some molecules that are
00:16:17known as proteins that all had a similar chemical composition and then you would find this stuff that they called nucleic acid and and people just didn't really know what it was for you know and and actually you know even in the mid nineteen hundreds a lot of people
00:16:33thought proteins where what genes are made out %HESITATION an attack that took some elegant experiments to %HESITATION to demonstrate now actually it's really if you transfer DNA from one microbe to another you transfer that trait of the proteins don't matter and and so then once we figure out
00:16:54the structure of DNA then all the sudden we can get down to the molecular details of how genes make heredity possible in other words that it's almost like genes are like texts you know they're they're made up of these units that that where they're like letters made up
00:17:16from a four letter alphabet and we have you know over three billion letters in our in our DNA and change the letters %HESITATION or cut and paste chunks of text and %HESITATION you get changes to to us and and those changes can be passed down if the DNA
00:17:35is being faithfully copied right and SO three billion a three billion base pairs right in our in the human %HESITATION DNA and but we talk about only having a twenty thousand genes so I I I'm gonna ask everybody I'll just I ever talked on the podcast to explain
00:17:53this because it took me a long time to get it right explain the relationship between the base pairs in the DNA in what we called genes yeah it's it's kind of messy but you know biology is messy yeah so %HESITATION so so the the the way the people
00:18:13traditionally think about genes is a stretch of DNA that encodes a protein and so you know every every protein is is encoded by a gene %HESITATION it is true although sometimes you get proteins that are made by combining genes together and all sorts of stuff you don't need
00:18:33to get into but in any case %HESITATION we have as you say twenty thousand of these protein coding genes and they only make up about one percent or so wondered what a two percent of the joy of art of the human genome so then the big question is
00:18:51what what's all the other stuff yes and yes so %HESITATION so some of it you know maybe ten percent of it is has functions of its own actually some of them are also jeans is just that they don't go the full process towards making proteins you have thousands
00:19:18of genes we don't know how many that actually %HESITATION in code R. N. A. molecules okay so you you may be used to think you are in a as part of the process to make protein energy yeah go ahead you got a gene made a DNA you make
00:19:36a copy in our day which is a single stranded version of DNA basically and then use that are in a as a template for building proteins out of a different set of molecules cramming us that's and that's that's true %HESITATION but it turns out that sometimes our cells
00:19:52will make an RNA molecule and then that's it %HESITATION and that not only that's it but that Arnie molecule has a really important job to do so for the for example in in women women have two X. chromosomes they need to keep one of them shut off or
00:20:09they're gonna basically poison themselves with too many proteins from the X. chromosome men only have one X. comes so there are so there are these Arnie molecules basically or wrap around the the X. chromosome one of the X. chromosomes in women and silences and so you know we
00:20:30know that at least some of these are a molecules plan apart job that's those are more genes but that still leaves you with a lot of the rest of the genome said some of that DNA is really important as kind of genetic switches for turning on and off
00:20:45%HESITATION jeans %HESITATION elsewhere in the genome up and then the rest you know a lot of it is probably what scientists would scientifically called junk there are a lot of them are dead jeans their genes it mutated and just are useless now and we just carry them along
00:21:05some of them are actually descend from viruses viruses in fact our DNA and make copies of the cells that get passed down %HESITATION and %HESITATION just spread all over our genome and and broke it up with all sorts of stuff that we don't actually it's %HESITATION they also
00:21:25could be codes that were injected by aliens billions of years ago to be activated some point in the future right yeah right now I haven't seen the papers on that yet but %HESITATION I may be seen a pre print I have given I'm giving it rules here Carl
00:21:40you should write all right I'm gonna get a I'm gonna have to scoop in century but it's a good reminder that you know we're not intelligently designed at the cell is kind of a mess that has been put together over billions of years and DNA doesn't care that
00:21:55its job is to in code teens into proteins it does whatever it wants to do so or whatever it needs to do to make things function so some of the DNA is making proteins some of its making RNA that will do something some of it's just going along
00:22:08for the ride because it keeps getting copied all the time right yeah I mean it it's hard to believe but the cell is a lot sloppy or than we think of it as being you know a lot a lot of the DNA actually is used by ourselves to
00:22:25produce our name molecules and then the cell just Emily shreds all that are in a because that that those were just sort of accidental %HESITATION member just not they didn't really have any function so %HESITATION you can have jumped in a shooting off our innate molecules but like
00:22:42they don't serve any yes so they just you know the the fact the cell just sort of like manages this chaos you know by having certain proteins that kind of go around and say like are you are you supposed to be here and you know if not then
00:22:57they just shut him and and just recycle it to to make Marty molecules so %HESITATION yeah it's not it's it's and if if you really get to know cells intelligent design becomes kind of laughable and so okay so we have this idea that the coding parts there there
00:23:16are parts of the DNA stretches of DNA %HESITATION many many base pairs at once that will code into a protein there's probably a an informal an incorrect idea I'm short none of our extremely sophisticated and well educated mind scape listeners would have this idea but some people might
00:23:34think that there's a direct map from a gene to a trait to you know how big are knows are what color hair is or how you know charismatic we are it's more complicated than that right for the most part yeah it is not more complicated I mean you
00:23:52know we it's good to learn about Mendel and in high school but you know I I do think that it's going to be important for schools to take students beyond mental now that people are getting their DNA tested by companies like twenty three me %HESITATION he can't really
00:24:11understand those test results if you're just relying on people and experiments right in other I mean we you know your blood type sure it's like you know there's one gene and and they're different versions of the gene and that that can determine your blood type okay no problem
00:24:27but %HESITATION but for most of the traits that we actually really care about or are you think about %HESITATION and even some seemingly simple ones like height %HESITATION they are influenced by many many many many many different genes and %HESITATION so that %HESITATION yeah you can say that
00:24:48%HESITATION I have to do I have the tall gene press just meaningless but so we bought ourselves up to about as you as you infer imply the level high school biology you know what people sort of remember %HESITATION we have a DNA we pass it along and I
00:25:04think that you know even if there is some complicated nonlinear map from the genes in our DNA to our traits people still have this idea that basically there's a molecule the DNA and from the molecule that's not that just makes us right but we know a lot more
00:25:23than that now also right I mean there's various ways in which the thing that we turn into is more than just what's encoded in our DNA in any straightforward way is that an accurate statement yeah yeah definitely I end and you know when we were I mean I
00:25:39it's funny you know like if if you say to someone %HESITATION %HESITATION you have two eyes you must have gotten your two eyes from your parents they're gonna look at you funny like what it doesn't make sense you know the fact is that you do get you didn't
00:25:54get your two eyes from your parents but when we when we talk about %HESITATION you got this you got that from your parents were really more interested in the things that are different between people so that we can say like %HESITATION you are tall and your great uncle
00:26:09Bertie was tall so we must have got it from him even though of course Bertie is off to the side or whatever my book to beat my point being that %HESITATION is that we we we just get kind of confused about what it is that we're talking about
00:26:28when we when we talk about these these traits and the fact is that you know you might be tall like your uncle Bertie is tall I'm sure partly because of of the jeans you inherit but %HESITATION you know maybe you and your uncle Bertie also I have the
00:26:46privilege of growing up in a %HESITATION at affluent society an affluent family you had good diets you got medicine when you're a kid and so that you have the opportunity to grow to be tall %HESITATION because the fact is that you know all over the world the average
00:27:07height of people is several inches higher than it was a century ago and that's not because we are now inheriting a different set of genes it's just that in there and that respect the world got to be a better place %HESITATION and so you so you have to
00:27:24sort of take into account the the the combined influences of genes and environment or actually as Shakespeare once called it nature nurture we'll we'll get there but I think that even at the level of nature even level of our inheritance our genetic inheritance %HESITATION I I you know
00:27:46I'm learning about from your book among other places how complicated that is for example the idea of mitochondrial DNA right we have these little sort of genetic stow aways in every single one of our cells and we hand them down to subsequent generations that's right that's right so
00:28:02yeah even if you just limit yourself to genes and heredity be a lot more complicated and strange then we learned about so mitochondria we have dozens or hundreds of them in every cell and we depend on them for survival there the little factories that generate fuel for our
00:28:26cell %HESITATION you know using oxygen and and various nutrients to to build to build fuel that we then Burke are they do lots of other stuff too so we're in the cell yeah absolutely and %HESITATION the weird thing about them welts several weird things one is that they've
00:28:47got their own DNA in them %HESITATION that's that's aside from the DNA that's tucked away in the nucleus so they've all got their own DNA and if you look at a cell you can actually watch mitochondria divine on their own and they make new copies of their own
00:29:02DNA for those new daughter cells and you might say like whoa that doesn't make sense that sounds like bacteria and like yeah yes what they're bacteria exactly like about one point eight billion years ago when we were single cell the ancestors mitochondria somehow ended up inside of ourselves
00:29:21and some maybe some kind of symbiotic relationship kind of like you know if ccleaner fish they go inside the miles a bigger fish and %HESITATION and then they became basically permanent residence so that they couldn't live outside of ourselves anymore %HESITATION and is it as if that wasn't
00:29:41weird enough %HESITATION you know when as when a sperm approaches NA gets its swimming furiously and is using that mitochondria to generate that fuel the swim %HESITATION so the only way I can get you **** uses mitochondria and then it reaches the ache and it jumps in its
00:30:01chromosomes but then it also destroys its own mitochondria it just rips them apart so both the sperm and the egg have separate mitochondria from dad and mom right and the sperm do not deliver their mitochondria into the ache lazy **** well it it's it's puzzling because you know
00:30:24we are when you look at our chromosomes we are a fifty fifty split between our parents but you look at our mitochondria it's all month just all mon so mitochondrial inheritance is not sexual reproduction exactly exactly it you know back to it for some reason we we keep
00:30:47out one of the parents from that process %HESITATION and it's interesting because what that means is that you know your mitochondria is is extremely similar to your mothers and your grandmothers and so on and so on so on because you know free with your chromosomes in every generation
00:31:08the pairs of chromosomes they shuffled some other DNA together right and so they swap pieces in this process called mitosis and so %HESITATION so after several generations you know your did you do your you know chromosome number two doesn't really look all that much like your great great
00:31:28great great grandmother's crime some to %HESITATION but %HESITATION but mitochondria basically the same I mean and and so you could there really powerful for tracing genealogy for example %HESITATION you know you could see the are %HESITATION you can say like a hot well this person has to be
00:31:48the child of this woman I mean there's just no two ways about it and and yet it's a it's a you know son signed as you're just looking at the basic questions about her editor like why why why is this a one line with the sperm not give
00:32:06the mitochondria what what why is it only then mothers and %HESITATION yeah there's some interesting theories about it I mean one theory is that %HESITATION if you have two batches of mitochondria inside a person coming from different people yeah %HESITATION they're going to not play well together that
00:32:26that they're gonna operate differently and that could actually cause problems I mean there's an ex right when we when we wouldn't meiosis happens miosis is the leading of this cell into a little sexual reproduction cell right so you know we split our genome in half and then they're
00:32:42gonna re combined with the have from the other parent and the mitochondria kind of our and participating in that process so it's you know dad's mitochondria moms are just there separately and they they might come into conflict like you set right right I ain't you know there are
00:33:00there are there are %HESITATION it's interesting you know there are we we we think of sort of mom and dad's genes as as you know playing nicely in our own genome but you know there are there are conflicts between the genes in our parents and evolutionary complex %HESITATION
00:33:17sentences conflict between our actual parents to yeah I now think about it hi RD in a you know %HESITATION you know sometimes we'll be like you know dad's genes are babies are driving kids to grow faster because that's good for the father's long term evolutionary benefits that the
00:33:37mother meanwhile if them as mother is is has to carry yeah the children thank you has to be pregnant like do much gross is actually like can really drain her resources and may mean that she has fewer children over her lifetime and so you actually find that out
00:33:56the man's copy of a gene is turned on woman's copy is turned off inside the child it's so it's like this tug of war going on %HESITATION short just a try just to try to is that finds a sort of optimal thing %HESITATION and then sometimes you actually
00:34:11find if there are there are genes are pieces of DNA that basically just totally break Mendel's law completely and just sort of override that sort of fifty fifty kind of split between which chromosome ends up you know in in an acre sperm %HESITATION this was illustrated with the
00:34:35discovery once of of certain kinds of flies certain strains of flies that where they would almost all always produce daughters and I do like %HESITATION what's going on here and it turned out that there was a gene that was basically hi Jack was sitting on the you know
00:34:52on the female chromosome in in in flies and was sort of basically %HESITATION insuring that the slide did not have any sons because if there if there were just daughters I would spread this gene further Sir the ultimate selfish gene well this makes sense right I mean we
00:35:13are you maybe make sense maybe I'm I'm leaping ahead too far but we have this kind of game theoretic way of thinking about not just the struggle to survive as organisms but we can we can end the selfish gene way of thinking think of it as the individual
00:35:29genomes trying to pass themselves down and you know mom has a genetic set of information and so does dad and they both want to win and in human beings in mammals there's this rough equilibrium that we've reach to where %HESITATION children %HESITATION fifty fifty male and female but
00:35:44that's certainly not universal across the animal kingdom is for different equally be a you could buy imagine reaching where the struggle plays out in different ways sure and and actually there are some animals that adjust the ratio of their offspring just depending on what their environment kinda looks
00:36:04like my so there there are birds that you know is it in effect what they're doing is looking around and saying like hi I think I need a lot of daughters to stick around and to help me raise you know my other checks and voila incredibly they produce
00:36:21out more daughters and sons and then there are other situations of the person who's more sons and daughters you know and then the Suns fly off I'm so yeah I mean it's we you know we we we like to think about %HESITATION we like to take biology and
00:36:39put it into categories and and try to come up with absolute so you know Mendel's observations become and the law or or males and females become the sort of absolute categories that you know you could never have any exception to I mean we we keep doing that I
00:36:56think we just have a very you know brains it really like categories but in a heredity just does not work like that yeah and and you know yeah now there are some patterns that kind of repeat themselves a lot but a lot of times those patterns are the
00:37:12start of the service stable balance produced by competition that sort of works out into this this almost like a detente well I talked with illustrator in episode three of the podcast we talk about inter sexuality and how the fact that the idea there's two sexes right that's a
00:37:31convenient fiction it's it's very useful to good approximation but if you gonna try to be a little bit more careful there's a whole bunch of stuff in between in different ways you can be in between and and this reflects I I think that philosophically this is just a
00:37:43really important point that you're bringing up that we organize the world be human beings for our comprehension because it's easy for us but as we try to be more more accurate all those complications going to become more more relevant to a better understanding yeah and and I noticed
00:38:00that a lot of times people will justify these absolute categories by saying like well look like this is just nature you know this is this is biology after just accept biology and like whoa like you wanna talk about biology take a little tour Shelley and Andrew my six
00:38:18hundred page book on in here absolutely absolutely I mean the fact is that heredity itself works very differently in in %HESITATION in a lot of different organ organisms and you know the the irony is that like this is this is one reason why Mendel was forgotten actually so
00:38:37this is this is this one of these these incredible ironies is that mental study peas and again he was like oh my gosh look at this mathematical thing that's happening any road to one of his mentors and his mentor is like %HESITATION I know that's interesting I'm not
00:38:56sure what to make of this is what you see if you can replicate this you know like if if this is what you say it is then you ought to be able to find it in another plant right so mental I guess agreed with that anyone studied another
00:39:11common garden plant %HESITATION %HESITATION %HESITATION and it turned out that this this other one %HESITATION hawkweed anything I forget the name now it it doesn't reproduce and then need to sort of sexual way that peas to it has pollen impala is sort of like the plan to go
00:39:32in a sperm and so they have male and female again needs and and they have to you have to have fertilization but in these other plants %HESITATION once fertilization happens the the ideals that the eggs as it were just basically just check out any mail DNA they don't
00:39:53use it so %HESITATION they they do my %HESITATION says you know it within their own jeans and SO base there they're kind of like clones except that there's %HESITATION shuffling their DNA with every generation so you know like boom like those lovely three one patterns and mental so
00:40:12the peas they're just not there at all right when he looks at another species and then it's like huh and %HESITATION you know you're magic if he'd picked another species that was very neat about you know the work like peas did that he might to gain more traction
00:40:29%HESITATION but now I mean he he was he was forgotten for basically fifty years it's good to know that the deflationary role of mentors has not changed in academia yeah over the centuries that's I think I've done that to my students sometimes love the idea the mitochondria as
00:40:44important as they are these stow aways that I mean they're basically living their own lives right there handing down their own %HESITATION genetic inheritance and it's part of what makes us who we are and so forth are there other examples of that I mean I know that we
00:40:56carry around a whole microbiome a whole set of little money cellular organisms that %HESITATION function in us but my impression is that we kind of build those up throughout our lives we don't actually get those from mom and dad well if you know that is the big question
00:41:16right now %HESITATION and any other people who are trying to really nail that down at the moment %HESITATION because you know it is true that %HESITATION you pick up microbes everyday army you're picking them up off your keyboard in your door knob and you're shaking hands or were
00:41:35you know you're having yogurt I mean like we're just yeah we're %HESITATION we're just swimming through a microbial ocean and all you you don't need me in particular you mean all the listeners out that's not my keyboard that is worse than average right well I've heard that not
00:41:51so %HESITATION it is so so the the thing is that %HESITATION %HESITATION we we also know that there are lots of species that passed down certain microbes as faithfully as they do their own jeans my favorite example is cockroaches okay so yeah cockroaches actually depend on one species
00:42:17of bacteria to help them to eat food because the bacteria can actually make some of the compound they need for proteins out of their food that the cockroaches don't have the genes to do it so they totally depend on these bacteria and in fact they actually build special
00:42:33organs for these back here to live in and the back you're actually like embedded inside the cockroaches on cells in this organ and when it comes time for the female to produce her aegs something incredible happened some of the cells that are carried these microbes they just start
00:42:55crawling and they make their way through the cockroaches body to the cockroaches eggs and then they open up and they basically deliver these bacteria into the aches and so after these aches get fertilized by a male cockroach then the cockroaches born with these bacteria ready to go %HESITATION
00:43:17just like we are with our mitochondria biology is very scary mind blowing in there you know I I really you know the the the best book on all of this is %HESITATION and young's book I contain multitudes on for me what interests me in particular about this is
00:43:37to think about this as another one form of heredity another channel of heredity thank you got your own jeans quote unquote but then you have these bacteria yeah no we don't have anything quite like that except for mitochondria that we know unknown but right but maybe there is
00:43:55something like her ready in the way that some of our bacteria and up inside of us %HESITATION inside just trying to figure out for example are human embryos sterile out when they're in the uterus like that it the evidence is not clear what is clear is that as
00:44:15as a baby moves through the birth canal there during %HESITATION delivery it gets slathered in bacteria and %HESITATION this is some of that back here goes into it got and and %HESITATION and there are certain forms of bacteria that the mother encourages to grow in the birth canal
00:44:34and not only that but %HESITATION but the mother's milk contains bacteria as well as well as bacteria food and other words sugar is that in the mail that babies can't adjust themselves but bacteria can't so I'm so there is a debate right now whether there might be you
00:44:56know certain species that are are are being put into babies early on and and sort of our kind to find our own species that way it's a very %HESITATION romantic picture you are painting there the miracle of childbirth this so enhanced by a scientific understanding it's really great
00:45:14%HESITATION I bought it and read it raises some very %HESITATION and practical medical questions you know caesarean sections are are exploding in countries like the United States and so you know you're so those babies are not getting that exposure %HESITATION and so there's a question like will does
00:45:30that matter you know %HESITATION can you still pick up those species just by being handled by your parents and other people or or does that not getting that seating at the beginning is that a is that a problem %HESITATION because you know if you're microbiome then isn't quite
00:45:48right when you're young I can lead to albums throughout your life you know your immune system may not work properly for example it's still thought to be true that the number of unicellular organisms and our microbiome is more sells it then human cells in our body actually no
00:46:07I I heard rumors that that had gone away that that thought yeah yeah so you know and I I and other people I had when we'd write about the microphone and we always say like you know your micro that number your own cells by ten to one which
00:46:23you know it's always fun to say %HESITATION turns out probably not to be true %HESITATION it it's just it's probably more close more like one to one that we have about thirty seven trillion cells of our own %HESITATION conquered own human cells it might be around the same
00:46:42you know I don't know thirty forty million bacteria %HESITATION you know I don't I don't that doesn't count the viruses in the fungi and all the other fun creatures that are inside of us so %HESITATION you know the final number of that full microbiome might be higher but
00:46:59its not attend the one thing anymore but a but a body %HESITATION biological body is a complicated open system it's %HESITATION it's %HESITATION ecosystem all by itself it's a we're a little bus that is carrying around a you know a whole world of little critters talking to each
00:47:15other and evolving in doing their own things yes but it's not a totally random collection of critters %HESITATION you know like the same species in the same strains tend to turn up again and again and people and I mean might your biker Brian's going to be different than
00:47:33mine but %HESITATION but not too differently you know and so you can like if you look at the human microbiome this compared to like a chimpanzees %HESITATION they're they're they're gonna be a lot more similar to each other than chimpanzees are and it seems like there are we
00:47:52have filters right you know so not everybody gets to see in the bus and then there's also the idea that we're learning more and more that just and %HESITATION information in our DNA even with just getting back to the the the sort of genetic part of inheritance there's
00:48:09more to it there's more to how we pass information down there's the whole story of at the genetics and so forth %HESITATION I I hear that you're advocating the people take epigenetic yoga classes so they can pass down new things that they learn to their %HESITATION children is
00:48:25that right many people are saying that right now I am I I yeah yeah right right now I think you should you should you know take epigenetic yoga feel like it but don't think that your kids are gonna be better for it %HESITATION yeah so that we can
00:48:43learn something and pass it down right yeah that we could have an experience that alters how our genes work in that alteration can get passed down to future generations that's that's the crux of of epigenetics an heredity %HESITATION you know and and it's it's it's tricky and I
00:49:03explored in in my book and and you know it's it's %HESITATION %HESITATION is definitely the %HESITATION good evidence for it happening in plants it's good evidence for it happening in little teeny tiny worms %HESITATION when you get to mice there's there's some very tantalizing experiments I mean so
00:49:26for example %HESITATION there's one experiment where %HESITATION scientists would would expose male mice to a certain odor and then give them a shock and then they learned is to associate the order with the shock and then they took sperm from the mice and use that in in vitro
00:49:45fertilization and then produced mouse pops and it seems like the mice in the next generation kind of responded oddly to that same odor %HESITATION and so the claim was that somehow that learned memory that learned association about that smell got passed down to the mouse pops %HESITATION you
00:50:07know and when that paper came out the journal put a mark on the cover a reminder to the market Mr the mark sterling mark %HESITATION so is right says so Lamarck was a French biologist who preceded dar when he was %HESITATION most active in the early eighteen hundreds
00:50:28%HESITATION and came up with his own theory of evolution which depended a lot on what's known as %HESITATION the inheritance of acquired traits and so %HESITATION so he had a classic example that you know it giraffes stretch their knack to reach leaves there's some sort of nervous fluid
00:50:54that causes their their next to get a little bit longer you can think about it that like like building up muscles and then %HESITATION and then that then those giraffes we passed down that longer neck to their descendants and so then over many generations the dress with a
00:51:11doctor and their environment by getting a longer neck %HESITATION and so many other claim my guess is that well mice you know are adapting to their environment %HESITATION by learning about you know the risks that they face and that that their offspring are inheriting that knowledge right %HESITATION
00:51:31so that's the basic idea and how would this work sort of at the molecular level for the mice is a popsicle the mice pups mice babies are published okay I learn something so it's a matter of obviously the DNA or not being altered as you as you smell
00:51:47something your DNA is still your DNA but somehow there's some information being passed on to the next generation that is not in the DNA is somehow in the chemical make up of of %HESITATION what goes into making a little puppy yeah yeah yeah %HESITATION I I don't think
00:52:07that if you call if you call them those puppies at at at biology conference people by look at you funny thing could be done we'll start roomy and realize that yes there's an impostor in our ranks that's a cosmologists get out yeah yeah so %HESITATION he is so
00:52:23and so the guy the we know we know that that genes are attended to by lots of molecules in the cell you know jeans just don't take care of themselves and so %HESITATION there are proteins for example that will clamp on to jeans and they can such a
00:52:45shot them down there are %HESITATION other places the proteins latch on to DNA and they can switch Donna Jean %HESITATION you can coal oil DNA around schools and then basically anything that gets coiled up any gene just can't be used to make a protein because it's just all
00:53:05tucked away and so %HESITATION and those changes can be very long lasting like when a cell divides those same controls will S. in effect be inherited by the two new cells so that's why your skin cells when they divide they make skin cells they don't you know make
00:53:26brain cells or or two six cells or something you know they get so so we know that epigenetics really matters a lot there's no question about that and so the question is could these kinds of process sees you know who %HESITATION change the way that genes are being
00:53:44used and then cut those changes you know those protein those coils or whatever get passed down through the generations %HESITATION we don't know yet %HESITATION we did the mechanism for it it's I mean is it's it's especially for mammals it's it's kind of hard to figure out how
00:54:03the mechanism would actually work %HESITATION and you look at a mass experiment I mean all the critics of this kind of researcher says like whoa so you're telling me that there's this change that that is happening in the mouse is brain the Daddy mouse is very and and
00:54:19that somehow then that is getting communicated into Daddy mouse's sperm and then somehow that is then making its way through fertilization through the development of an embryo through the development of a brain and then somehow it's getting plugged into it back into the brain and the same circuits
00:54:39that Daddy had being altered %HESITATION the and allows scientists to say like whoa that that doesn't make any sense at all right but this is something is being study will try to figure it out yeah but in the meantime there's a genetic yoga like you know there are
00:54:56literally like psychologists who will help you to undo the epigenetic trauma five you that your grandparents passed down to you like this has totally saturated pop culture and I don't honestly know how it happened because you know at the genetics is messy and complicated at and and the
00:55:13language is totally inscrutable and yet you know when I give talks like half the questions I get after after the talks are what about epidemics and look I'm writing a book about quantum mechanics so the idea that crazy abstract ideas are going to hijack the popular culture is
00:55:29not foreign to me any any tips well quantum epigenetic yoga might be a good seller right mile gone with that so dark and in there and will be buying yachts %HESITATION need any moment so okay we need to we need to trade we need a patent that idea
00:55:45right now okay author author of the book is I will edit this out on the podcast so no one hears it and steals our great idea it sounds like though %HESITATION even in principle if you handed a computer a complete list of the six billion three billion base
00:56:02pairs in our DNA the G. C. T. a %HESITATION letters in our alphabet a computer with perfect knowledge that would not be enough to predict what the organism would look like I mean it would be missing the mitochondrial DNA it with the single source of chemical signals that
00:56:18could be passed down through the body but I mean it's so weird it sounds like we're learning how much of the organisms predicted by that probably a lot right but %HESITATION certainly not the whole thing yeah and and and the way this this is one of those deep
00:56:33questions in the history biology %HESITATION you know how much of a of an organism is basically %HESITATION determined at the very beginning and how much of an organism's end result is just the emergence through development you know through and and you know it's you know I was always
00:56:58the answer is both but it's complicated you know and in in the in the sense that you can there are a lot of things that you can predict based on DNA %HESITATION those predictions mainly are not like you know I can't like predict what color shoes you're wearing
00:57:13right now today based on your DNA Sean but I bet if I looked at your DNA I could get a pretty good idea what your eye color is %HESITATION and I might be able to you know make make some very crude predictions about the influence of your jeans
00:57:32on on your height %HESITATION I couldn't tell you how tall you are because I don't know if your parents you know fed you properly %HESITATION but you know I I there there there are things that you can predict out of out of DNA but then there's this uniting
00:57:49did the DNA makes you know the cells make proteins are name molecules from the jeans and they're the cells are talking to each other and and they're taking in cues from the environment cells are migrating through the body and all sorts of all sorts of crazy stuff is
00:58:04happening and and all the genes are responding to all of that era and that is how we end up the way we are so yeah so you know if someone you know I had my genome sequence I'm sure nobody could make any predictions about me %HESITATION from that
00:58:23yeah right I do want to that that's right I remember this from the book so when you say you had your genome sequence so like your special here because he really had the full blown %HESITATION treatment if people do ancestry dot com or twenty three me or any
00:58:38of these things they get a little bit of information about their Dino but they do not get a list of three billion %HESITATION ACG tease right I mean they get some some sub knowledge of that did do you actually have a printout of you know all three billion
00:58:53base pairs in your DNA I do not have a print out I have a hard drive metaphorical and is being metaphorical yeah well well if I printed it out it would you know fill up you know dozens and dozens of books I mean there would be a fine
00:59:11art project but %HESITATION can use a small font it's okay yeah and it would be kind of hard to you know do a search function on that so I preferred preferred to have it on that hard drive because then I can take it to scientists and say like
00:59:26okay you know let's let's play around this data here which just so happens to be my genome and show me how you discover things in human genomes %HESITATION by analyzing this sort of data and it's been a fascinating experience but it is a very different thing than getting
00:59:43your DNA sequence from a place like twenty three me %HESITATION what twenty three may or ancestry does is they do something called Gino typing so basically they look at maybe that's maybe a million markers million spots in throughout your genome and they tried to they look at see
01:00:04what what your variant do you have at that particular spot %HESITATION and so it's you know it is kind of a high level survey of your genome but you can learn an awful lot %HESITATION one of the reasons you know learn an awful lot is because we we
01:00:20we pass we tend to it like share similar stretches of DNA so so if you've got you know a string of variance all in a row chances are that that whole segment of DNA is identical to somebody else has the same variant right and so you can kinda
01:00:38you can infer a lot about what's in between those markers well when you get your whole genome sequence that means that you're trying to figure out as best you can every single letter in your genome %HESITATION and and that was that you can discover all sorts of deeper
01:00:57things about your genome well in one of the deeper things you could discover is that you are susceptible or even almost inevitably going to have some disease that might affect you at a certain time of your life and so there's this question of what do we want to
01:01:12know like if if you could the the philosophers would come in and instantly say the version of the question to ask is if you could know you were going to die %HESITATION exactly a certain day would you want to know that it's that information you want some much
01:01:26cruder version of that might be available through this %HESITATION looking at our genomes that information is really only available to a small fraction of the people who get their DNA Gina type to get their genome sequenced because %HESITATION is it the genes that really that strong impact on
01:01:55your health let's say you know we're talking about genes that cause Huntington's disease or genes that raise your risk dramatically of getting early onset Alzheimer's genes that dramatically raise your risk of getting certain forms of cancer these are rare right %HESITATION the unnatural selection is not fond of
01:02:17these genes for all these reasons says that they're further rare and and %HESITATION and so %HESITATION you know I I when I got my genome sequence the first part of it was was doing it at I guess I did it as part of a conference and I think
01:02:35there were like forty people are going to this conference you also got their genome sequenced %HESITATION they were getting the right data but they were getting these interpretations from clinical geneticists there are like forty of us and I think if I recall correctly maybe like five people were
01:02:52told like okay you know we're gonna sit down with genetics counsellor and make some plans for you to talk to your doctor because there's something you need to know about how's your life insurance plan looking yeah right right I mean for the rest of us those like mine
01:03:09you know like you don't have any easy read Lee you don't everything that really jumps out you know as as what is what they would say you know there's nothing where it's like Hey that gene that's big trouble now you know I have plenty of genes that have
01:03:22been associated to where you know raising my risk of this disease or that by some modest amount but that doesn't mean that I'm going to die if any of those diseases and we also have a variance that lower the risk for certain diseases to and and so %HESITATION
01:03:39so you know he the and that's you know that is going to be how most people are going to %HESITATION but that's mostly we're gonna find when they when they get their DNA sequenced and it's going to be %HESITATION it either into their a lot I'm concerned that
01:04:00people do not make one of two mistakes one mistake is to be like Sir angry and irritated that they didn't find anything in their genome you know it's like really like my deal is much more interesting that you're making it out to be yes well you know like
01:04:17like this isn't like a status thing like it's not like you want to go to the doctor's office and and get terrible news you know and like it's not like you feel like you're you should feel happy if if they say oh you're fine see later %HESITATION and
01:04:30also %HESITATION did the flip side of that is that sometimes people will will get in these %HESITATION reports are made to do their own research and discover they have a gene that is associated with some disease that you know it's just say like colon cancer %HESITATION and they
01:04:46say oh my god that's it I'm gonna die of colon cancer like no no no you like think you have to you have to dig down that extra level and say look we'll exactly did this study find you know like do you did find that like people have
01:05:02this variant had into a slightly higher risk of this disease yeah and also like how big was the study like if if the a lot of these studies when their preliminary it's just like a hundred people their tiny and you know tiny studies are often wrong and so
01:05:21there are plenty of their mutations that were thought originally to cause diseases that we now know do not so you know you got to think about all these things when you're looking at these results and that's kinda gets back to me and my how how I feel that
01:05:37like our our high school grade school genetics is just got a step up its game because these things are not just abstractions that you learn about high school never think about again people again these results in in their email inbox right but also isn't it isn't it maybe
01:05:54an antiquated kind of worry because %HESITATION I will recently I bought new running shoes so I went to the Nike website and they let you actually customize your own shoes like me what color front and what we what logo is on the bottom and stuff like that so
01:06:10within a couple generations will have a website for doing that for our babies right we'll just be able to pick what %HESITATION different features you want them to have edit the DNA and get whatever may be the one I I I am sure that there will be people
01:06:25who are offering that if if the laws allow yeah I don't think that you will get the baby the of your dreams I think your baby will will just be your baby and and will be subject to you all the vagaries of of experience in biology and all
01:06:40the rest of it %HESITATION but you know we already have all sorts of %HESITATION companies out there that are offering really dubious claims based on looking at your DNA you know look at a few variants and they'll say aha like here's your special you know %HESITATION exercise program
01:07:01or or here's your here's your special DNA diets or are did there's even a company that %HESITATION called food line gnome and enough you seen them now they will recommend wine to you based on your DNA I bet you sorry how do you spell that I actually had
01:07:23to do it to look this up what is it yeah yeah yeah please do V. I. N. O. and ET vinyl right could be podcast months or down the road I like it %HESITATION well yeah I you may you may not want to play this episode because I
01:07:36mean when I saw a video for it I just thought well this is the way this the onion I I'm this this can't be real but it was %HESITATION and I know like I mean all these companies seem to be doing as far as I can tell is
01:07:54%HESITATION no looking in the scientific literature and saying like you know %HESITATION do you know the the here's a variant where people who had it tended to report a stronger sensation for bitter tastes and people did mine and then going from that to saying like here take this
01:08:13being on our %HESITATION and %HESITATION you know with exercise it's it's a very similar thing I mean yeah sure there are genes that are ex associated with all sorts of aspects of exercise you know the power in your muscles are how much oxygen you take in and so
01:08:30on and I'm sure that like there is a genetic element to great athletes being great but you know I when I got my genome sequenced the company that gave me that first sort of %HESITATION first layer of %HESITATION results before I took matters into my own hand they
01:08:53actually exert like your muscles are built for power sorry I didn't mean to laugh I was letting it it's something completely separate that was happening here yeah I'm sure I'm sure no it's okay John yeah I like it I mean you you that me and and I I
01:09:10mean like anybody was met me knows that my muscles are not built for power I mean it's just not the case and you know but what they're doing is they're just looking at this one variant and these these limited number of studies and not taking into account all
01:09:25the other genes that influence our muscles many which we don't really understand so yeah there's %HESITATION I I so I do worry about you know letting letting folks like that inmate who run these companies do the same thing with with you know designing babies tell us a little
01:09:44bit though about crisper and the reality of gene editing it is something that %HESITATION is is brushing at as very very quickly right yeah yeah I mean I only became aware of crisper may be six years ago or something and and and I can remember the thinking of
01:10:05me at first I was sort of puzzled by because actually crisper what it was %HESITATION it's it's natural thing what it is is is basically an immune system for bacteria they make molecules that can essentially %HESITATION store information about viruses and then use that information to you create
01:10:27new molecules that can zero in on particular stretches of virus denying cut it and I thought wow that's that's cool I mean microbes never cease to amaze me but %HESITATION but then some scientists said well we could use that %HESITATION and we could maybe cut whatever DNA we
01:10:48want and long behold they could they could zero in on particular stretch in the Dinning make cuts and then substitute in new DNA and all of a sudden they had this very powerful new molecular tool at their disposal %HESITATION you know scientists use crisper all the time now
01:11:06to do experiments you know they might say like we want to know you know which cell I'm sorry we want to know you know which jeans and a cancer cell are essential for it to survive as a cancer cell so they'll just use crisper to systematically cut out
01:11:24every single gene and individual cell lines and just see which one survive as as cancer you just can do that before I mean there's so it the impact is unbelievable %HESITATION and then people are starting to say like well can we use this to alter the genes of
01:11:42craps or of animals and dancers hell yeah and so and so the next step is what what do we do for people and one of the things you can potentially do for people is %HESITATION treat her editor diseases so someone has sickle cell anemia you take some of
01:12:02their %HESITATION their bone marrow status sells out these stem cells there can make blood you tweak their DNA so that they can now make hemoglobin that they need into their proper kind of hemoglobin because sickle cell anemia is caused by a misshapen kind of hemoglobin and that you
01:12:22put the the cells back into people and they make healthy blood cells %HESITATION that's that's the hope %HESITATION and their clinical trials I could start very soon on that %HESITATION and then the the big crunch you're the one that that you know understandably everybody gets excited and scared
01:12:43about is what if you could use these on embryos and change jeans and embryos and then you are creating an inherited change that will be passed down through the generations right yeah I gonna do it right it's going to I mean so at eco hi I have a
01:13:04kind of an extremist point of view on this because %HESITATION people say people raise this question that you just raised you know can we %HESITATION genetically edit what's going on an embryo and therefore change the person is going to be like and there's a sort of instant reluctance
01:13:18right it's it's like well of course that would be bad or at least it might be bad we should think about it we should you know will be very careful I'm not quite sure where the reluctance comes from other than this sort of squeaky miss right it sort
01:13:32of feeling that we're messing with nature and what I suspect is that some people feel that way some people will not feel that way and it's absolutely a hundred percent going to happen and a hundred years from now the idea of just making a baby a by randomly
01:13:50picking half of the DNA from mom and have to be made from dad and hoping for the best will seem hopelessly barbaric %HESITATION well you know when you know you're going to have to you know hope that %HESITATION you know life extension anti aging drugs %HESITATION advance really
01:14:08from quickly so that we can make a bat and see if it pans out you know yeah but %HESITATION in I I am what about these scenarios a lot %HESITATION partly they're just fun to think about and and it's %HESITATION and and you know it's it's it's what
01:14:27science fiction writers do so well and you know I I II there a lot of questions I have I mean I don't I I I I'm not is sanguine maybe the word as you are like in the sense that %HESITATION so for starters like crisper like %HESITATION crisper
01:14:47is is indeed revolutionary but %HESITATION it it's turning out to be to have some some problems %HESITATION it because it's it's paid it's eight people call gene editing but it's editing that involves shopping DNA and that is a pretty radical thing to do to DNA in cells don't
01:15:14like it I mean we this cells actually have all sorts of defenses against chopping up DNA because it can lead to all sorts of damage that can ultimately cause a sells descendants to become cancerous for example %HESITATION and not only do so you know there there are concerns
01:15:32about %HESITATION just have safe %HESITATION crisper would be in terms of like creating a line of cells you'd want to put in your body through crisper like you don't want to put in cells that are gonna be more prone to cancer that's probably number one problem number two
01:15:47there's a recent studies %HESITATION that %HESITATION showed that sometimes when %HESITATION scientists try to cut one particular segment of DNA out they cut out a long stretch that includes that that particular target %HESITATION and so you might be cutting out pieces of DNA that you really need and
01:16:12maybe maybe that when the DNA is getting repaired it gets kind of shuffled around in in ways it could be a problem so so okay so there's a safety issue and then %HESITATION then also there's kind of like the logistics issue you know like you know if you're
01:16:28saying I mean you know you're saying like how is this is barbaric so you're imagining a world where are you mentioning we're we're all say nine billion people %HESITATION all get in vitro fertilization no I mean read it your fertilization is a very difficult drawn out process right
01:16:48now %HESITATION it could get a lot better in the future but you know maybe not maybe there's some inherent sort of limits to do this %HESITATION it's it's not so my point is that Chris it wouldn't be Chris you wouldn't have crisper alone would not deliver you into
01:17:05that science fiction future you have to have all sorts of other advances in reproductive technology and stem cell research and all the rest of that %HESITATION before this could even be possible but I but I I have talked to biologists to say you know we're gonna look at
01:17:24we're gonna look we're going to %HESITATION look at crisper like vaccination in the future right yeah so I I think I I get absolutely the fact that it's not within the next five years or ten years right we will have to extend our lives we're going to see
01:17:39this thing come true and and I'm I'm also not sanguine in the sense I think that it's an on going to be an unalloyed good I look at you know this editing of our children's genomes as something it's a technology it's like cars or Twitter right there's going
01:17:53to be good parts about it or bad parts about it I just think it's inevitable I just think that it's it's like we have %HESITATION jumped off of the peer into the ocean and as we fall in we're debating should we get wet or not and that's just
01:18:08not a debate it is very reasonable to have we have other debates should we swim for short we try to climb back up the pier should we fight off the sharks but I think is going to happen and you know people are going to be trying to alter
01:18:20their children's intelligence and skin color and size of their noses and everything and I think that we're kind of dropping the ball a little bit on dealing with what the implications of that really are going to be well I mean I guess the question becomes you know if
01:18:37people really are going to try to do this if they can that you know should we pass laws to prevent that %HESITATION %HESITATION %HESITATION %HESITATION or do we have who could do we put regulations in place to to allow certain uses of it for certain things %HESITATION and
01:18:57then and then really you shifting from a scientific question to a social worker or a political one you know for example with we're dealing with that right now actually any people don't realize it but you know of gin genetically engineering humans has already begun %HESITATION because %HESITATION you
01:19:14know something we were talking about my country before it like so so mutations can cause mitochondria to become defective and so women can pass down %HESITATION defective mitochondria to their children and you can get these mitochondrial diseases which can be quite devastating they're all sorts of different ones
01:19:33that emerge from from faulty mitochondria so some years ago people thought well what if we were to do a a transplant in a transplant take that the DNA in the nucleus of an a and put it into a donor egg that has good mine a country that obviously
01:19:52you take out the nuclear DNA out of the eight direct first but anyway so so basically you're just get now you have an egg that has the mothers nuclear DNA chromosomes and another woman's mitochondria and then fertilize that people go out three parent babies which part in it
01:20:11but it's stuck anywhere in the we can debate about what it means to be a man but yeah in any case %HESITATION yeah %HESITATION in the United States that has been banned I mean you'd be that there's no there's no way that's gonna happen in the United States
01:20:31there's no way they're going to be researcher evaluation of that forget it that's that is dead in the water right now %HESITATION and %HESITATION you know there was a case of %HESITATION need of a doctor in New York who had done some research on this actually went to
01:20:45Mexico to treat a couple %HESITATION who the mother had a mitochondrial disease and so they Mexico doesn't have any laws one or the other about it so they did a kind of on the you know secretly arm and %HESITATION but I'm meanwhile in Britain they talked about this
01:21:09a very quite explicitly add discussions in parliament and they said you know what %HESITATION these diseases are so devastating and %HESITATION we we feel that you know this combination of mine a kinder from one women and chromosomes from another woman we're okay with that you know we don't
01:21:27think that violates sort of human dignity and %HESITATION we're going to allow this to go forward under a lot of regulation and so there's a university in Britain that has gotten a license they're open for business and so they will start probably babies will start be born being
01:21:44born soon sue this technology so you know I wonder like what's gonna happen with crisper right will it be will be the American version total ban will be then Mexico version like it's all kind of and I'll be you know unregulated black market or is it going to
01:22:01be out in the open carefully explicitly regulated you know %HESITATION and %HESITATION under under the guidance of government well and I think that's I I'm being a little intentionally provocative here because I think that people are there is a tendency for people you to sort of ask rhetorical
01:22:21questions and leave them hanging without clamped answering them or there's this other tendency which we in the United States love so much is just a bandit first and ask questions later for something like designer babies if it does become %HESITATION possible and obviously there's enormous scientific technical hurdle
01:22:38hurdle to getting there but you know I could easily imagine this band here and so okay someone set up a clinic in Mexico or the Cayman Islands or whatever and rich people go there and design their babies and poor people can't do it or even if it doesn't
01:22:52get banned anywhere like you alluded to earlier this just okay you can do it it cost a million dollars right that's how much that the effort is going to require and so that's the kind of inequality socially that %HESITATION is is going to be hard to deal with
01:23:07it's a little bit it hits home in a way you know the ability to make sure all your children are DO tall and beautiful that %HESITATION other kinds of inequality might not I I have a problem with the these arguments against crisper based on inequality because they all
01:23:29make it sound like we are living in and and the paradise of equality today you know what we're not you know like it you know it if you're if you Arkansas is concerned about in the quality like like it was time to get started now %HESITATION because it's
01:23:49not as if genes are the only thing that can influence the the success of of children later in life and and so you know and you know and this this raises the I I do think that this also raises difficult questions because you know if you say okay
01:24:07well it's wrong to let parents I use Chris Byrd to make their children let's say you know tall beautiful or whatever you want to dream that you could do with crisper I I I don't think that would happen but let's just pretend you could anyway %HESITATION okay so
01:24:24%HESITATION what about all the other %HESITATION it does vantage's that children of wealthy parents have that the ads that I help them to get ahead in life you know just you should do do we make those illegal %HESITATION should %HESITATION SAT prep classes be banned yeah no I
01:24:43think it's a very real but I I still think the analogy is not quite perfect I mean I get it and I think that we are a terrible society at %HESITATION at treating people equally right now though that that point is very very well taken but in America
01:24:57at least you know people grow up with this idea that some day no matter where you come from you could be a millionaire you could be president the no one goes up with the idea that %HESITATION you know twenty years from now my DNA will be better so
01:25:09there's a it's a it's this kind of obvious in your face difference between people which I suspect people will react to bury this early I I I agree and I mean I think part of it is that well you know part of the problem here is that we
01:25:24think of genes as being this sort of %HESITATION absolute definition of who we are it's not %HESITATION but but we also think about heredity and in the sense that like these kids will then pass down these traits to their kids and so on and %HESITATION and that really
01:25:43like strikes a chord I think because like I was saying before like her heredity is is such a profound %HESITATION saying to us in terms of how we define ourselves %HESITATION and so to be tampering with ready seems like one of the great %HESITATION yeah you get transgressions
01:26:03and and and that I think colors are our our discussion of this and you can see this and you know in the debates debates people app you know scientists who developed crisper actually have just in the past few years like had a series of international meetings there to
01:26:20figure out like what what's what's right what's wrong what should we do with with the S. and the overriding issue it seems it was what is this going to do to her ready which is so striking to me %HESITATION because it really tells you where our concerns are
01:26:37are located %HESITATION and %HESITATION I think it's a good question but %HESITATION you know I I on the other hand I mean I just I don't some people say that %HESITATION we're going to turn ourselves into two separate species you know you'll have the rich people can afford
01:26:56crisper will become their own species in the poor people will become a different species as our minds me of %HESITATION you know the time machine %HESITATION H. G. wells yes exactly you know what I'm talking about yeah but you know you know like a but good people but
01:27:10like that just people just don't work that way like animals in general don't work that way like you you like people have sex lots of sex and like people don't respect these sort of arbitrary boundaries when they're having sense like whatever genes get it you might get introduced
01:27:28into some rich person will either disappear entirely from the human gene pool eventually because that's what happens to most gene variants or we'll just kinda diffuse around all over the world after awhile because of just the way that people have kids together so %HESITATION so you know I
01:27:48just find some of these science fiction scenarios %HESITATION that people are talking about is if they're like real ethical questions to be silly frankly I think actually so I'm gonna I'm gonna go on the other side I think that %HESITATION even if they're wildly unrealistic and not mapping
01:28:04out the future I'm glad people are envisioning the craziest most extreme scenarios I think will help us sort of be prepared a little bit for %HESITATION the Brave New World yet to come well let me know but but but but you have to then bit okay you we
01:28:20can talk about these scenarios but then we have to take the next step and say like well okay but here's the basic are the basic facts of science to tell you that this is not even something worth considering you know for %HESITATION you know like for example like
01:28:34I I wrote an article for the times recently about studies on DNA and the and the link between genes and how long you stay in school there is a connection there we don't really know why there's a connection there and may and may have to do with genes
01:28:50that influence certain things that our brains are maybe even our parents brains we don't know but there's an association there it's interesting it's worth studying and you can actually like look at you know these million variance in people's DNA and actually come up with a score a sort
01:29:10of education score which which sounds very fancy like %HESITATION well I could use that to you now test some can a gardener and say like I you're never gonna make it to college so we're just going to put you over here in this this track and you know
01:29:24you just be content with your lot they'll be a ridiculous thing to do because this score yeah it only predicts I've small amount of the variation in how people do in school so chances are that your score would be were very wrong %HESITATION so yeah lots of people
01:29:42with with a high genetic score who drop out early from school there a lot of people with a low genetic score two going to grad school like it's just one variable among several so you know for people to say like %HESITATION okay well clearly we're gonna have this
01:29:59feature where every everybody's fate is predetermined well no no and it's it's it's not a scenario worth talking about just because of the basic statistics of what we're talking about so you know I'm all for talking about scenarios but you have to you have to be willing to
01:30:18to throw some out no I I completely agree on that I mean that that idea that you just said about sort of predicting peoples educational attainments on base of their DNA makes the vehicle no sense to me it's like taking a preseason power pole in some sports league
01:30:33and then saying well we don't need to play the games now we figure out who's going to win but playing the games actually matters also so Carl Zimmer or as we say around here Carl Bildt for power Zimmer thank you very much for a wonderful conversation so it's
01:30:48great to talk to you hours good talking to you again John all right bye bye bye

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