Paige Harden: The Genetic Lottery: Why DNA matters for social equality
Paige Harden, Image Courtesy of Paige Harden
"Click here to listen to the full podcast episode"
Paige Harden is Professor of Psychology at the University of Texas at Austin, where she leads the Developmental Behavior Genetics lab and co-directs the Texas Twin Project, where she explores how genetic variations influence our behaviours and lives. She’s also the author of a new book based on her work, The Genetic Lottery: Why DNA Matters for Social Equality which, it’s fair to say, has attracted a certain amount of controversy.
In it, she argues that variations in our DNA that make us different, in terms of our personalities and our health, can affect our chances of educational and economic success in life. Rather than ignoring these differences, or simply saying “well, if it’s genetic, what can you do about it?”, she puts forward some ideas for how we can use our knowledge about genetics to achieve more equitable outcomes for everyone. To start with, I asked her how we go about studying the genetic influence on our brains, behaviours and lives.
Paige: It obviously doesn't stop at the neck and most people already know that. I talk about this study in the book where Emily Willoughby, who is a psychologist at the University of Minnesota, She and her colleagues asked a sample of lay Americans, not academics, to estimate the genetic influence on diseases like diabetes or breast cancer, mental illnesses like schizophrenia, but also psychological traits like intelligence or personality.
Paige: And what's so interesting about that study to me is that people's answers were almost never zero. So most, at least Americans, think that genetics makes an influence, not just for our bodies, but also for our brains and our psychologies. And that on average you can kind of crowdsource guesses about how much genetics influences things and people are not wildly wrong, right?
Paige: So they intuit that genetics has a bigger influence on eye colour than political beliefs for instance, their estimates on average track what heritability estimates we get from twin studies. And I'll come back to that in a second, because twins being one method for estimating genetic influence on something.
Paige: So we exist in this weird state of both knowing and unknowing in our conversation about genetics above the neck. By knowing I mean that, again, most people have an intuition that genetics makes an influence for these things. They see it in their own lives. They see it when they observe their children. When they're thinking about why they're different from their siblings, when they're thinking about why the children in their classroom, if they're a teacher, are different from one another. But obviously within the academy, within academics, that's a very controversial idea and that disconnect is interesting in and of itself.
Paige: So when we're thinking about how do we go about studying this? We're talking about humans and we're talking about traits over which we don't have, thank goodness, we don't have strong experimental control, right? Like, so the plant geneticists can go in and they can say, okay, this is gonna be exactly your rearing environment and this is going to be exactly your genotype and I'm going to have genetically identical organisms.
Paige: And human behavioural geneticists don't have that exquisite experimental control which really raises questions in people's minds. Are we really successfully able to disentangle correlation from causation? Can we really say that genes are causing something about people's lives? The metaphor that I use for the title of the book, The Genetic Lottery, I use that metaphor for a number of reasons, but one of the reasons that I focus the reader's attention on that is that this shuffling process that you just talked about, the fact that your mom and your dad they each had two copies of their genes and they got shuffled together and you got one, you got one random draw from that and your sibling got another random draw.
Paige: It is being able to measure the genome and then look at how family members, parents, and children, siblings differ from one another in their genetics because of this random shuffle of genetic inheritance. That is really one of the most powerful tools that we have right now to say, okay, this isn't just genes are correlated with life outcomes, genes are really causing something about the development of intelligence, personality, how far people go in school.
Paige: So, you know, the old method was to look at samples of twins, usually identical twins versus fraternal twins, raised together or children raised by their biological parents versus adoptive parents. So that's kind of one type of natural experiment. These are people who have the same sort of social relationship as family members, but different genetic relationships.
Paige: And those types of designs I think are still really valuable, I still collect twin data. And now, because we can measure the genome directly, very cheaply and noninvasively from people's saliva, we can take advantage of this other natural experiment, which is this shuffling of genes between parents and children to look at, okay, If I happen to inherit this sequence versus this sequence, how is that related to how my life ends up differently than say my siblings who inherited kind of a different random draw from our parents.
Kat: So you've talked about using things like twin studies to try and even out this influence of nature and nurture. But whenever we talk about things like life outcomes, you know, I'm assuming there's not a getting more money gene or having a nice house gene but how do we tease out the nature from the nurture? Because you know, social inequalities must have a huge influence and also, you know, families that are living in poor areas and maybe their children are staying in poor areas. Like, how will we, how can we actually start to untangle some of this? Because, you know, I know about the principle of doing genome-wide association studies, find lots of people, you see who's got the trait, you see which genetic variations associated with that trait, but with something like life outcomes, how do we really start to tease this apart? Because obviously it's a really big issue.
Paige: Yeah. So, I mean, in one sense, they're never teased apart because they're always in the life of an individual. They're always obviously interacting. You know, there is no development without both genes and social environment. And also there's, in many ways, no way of conceptualising the long-term outcomes of genes without thinking about ways in which your social environment responds to you, to your sort of embodied psychology.
Paige: So, you know, in my mind, the goal of cleanly separating, this is nature and this is nurture, is really kind of the wrong goal. I'm more interested in, will we know that the "effects of nature" are sort of always bound up with what is our social context and vice versa. People who live in the same social context, who even are raised in the same home with the same parents go on to live different lives.
Paige: So I guess I would just reframe the question. We're not kind of surgically peeling away, we are not wielding some scalpel that says this is the purely biological bit, and this is the purely social bit. It's more like tracing If you start in different points, genetically, how does your life then kind of wind its way through the social environment, such that those kind of initial starting points can end up being, in part because of how they're responded to by the social environment, end up being consequential in the long term.
Kat: So this is really we're dealing in possibilities, not determinism.
Paige: Oh, always. Yes. I mean, so often when people are first introduced to genetics, they're thinking of, you know, they learn about genetics in the context of maybe single gene disorders.
Kat: The gene four, it's always the gene four.
Paige: Right! So you have PKU and you have, so you have this "inborn error of metabolism" or disease of metabolism and it's influenced by one gene with a very strong effect. Or something like down syndrome, which is trisomy, you have three copies of your 21st chromosome rather than two. And the thing about those sorts of genetic relationships is that they're specific. So this gene is the gene for this thing. They're pretty uniform. So if you have three copies of your 21st chromosome, you're going to have down syndrome and that's going to be true, regardless of whether you were born in 15th century France or present day North Korea, you know, it's kind of constant across time and place.
Paige: And they're explanatory, right? Like we can say, if I know something about what this gene is, I can tell mechanistically something about the biology of this disorder. When we're talking about genetic influences on our intelligence, our education, our income, those are entirely different types of genetic effects. They're not specific, they're not uniform, they're not explanatory. It's not like down syndrome being caused by a trisomy.
Paige: It's like how, you know, maybe Instagram makes you more likely to be depressed, but only for some people. And it doesn't guarantee that you're going to be depressed. It just raises the probability that you're going to be depressed on it and we have to consider context and the person. The source of genetic facts that we are looking at in modern human behavioural genetics are not "here's your wealth gene", It's if you got this constellation of genetic variance, to what extent is the probability of your life going differently changed. And it could be a big change, but it could be a little change, but it's never the cause, it's always happening and sort of in concert with the environments that people are living in.
Kat: So I want to dig into an area that gets pretty sticky, pretty fast. Because in the field of genetics over recent years we've seen people using genetic information, and genetics particularly, trying to put sort of quite a frankly, appalling racist spin on it. We've seen white supremacists using genetics as a way of categorising and discriminating against people. So is there a risk that when we start to do this kind of research, we're almost going back to the days of Francis Galton Uber eugenicist and this kind of thing, and really running the risk of starting to dig into information that puts people in boxes that they shouldn't be put into. How do we deal with this?
Paige: Yeah. I mean the short answer is yes in the sense that all technology has risks and a risk of being misunderstood and misused and misappropriated to kind of prop up narratives. In this case people seizing on genetic-y sounding information in order to say this is my support for my kind of racist idea about, really white supremacy is the reason way that it's most commonly used, in the same way that we see information on public health and virology being used by anti-vaccine advocates or the ways in which we see that, you know, the rise of social media, predictive algorithms can be used in ways that perpetuate algorithmic bias.
Paige: We're kind of hard pressed to think of an advanced technology that doesn't have both real risks of being used for harm, but also this risk of it's a technical field where most people don't have a super strong scientific foundation in it. So it's easy for people to come in and kind of come up with scientific sounding stories to support their argument.
Paige: At the same time some of the most, I think, powerful demonstrations of why those narratives about white supremacy are wrong come from genetics. You know, when you teach people about the amount of genetic diversity that exists within ancestral groups that are, at least here in the US, all lumped together as one race. When people are taught about the ways in which, you know, the genetic research that's happening right now really is limited to people who only have European ancestry and how much we just don't know at all about other populations.
Paige: I don't think we should undersell the fact that knowledge is power and that power could be used for ill, but also it could be used to combat these really pernicious, racist narratives. You know, there isn't kind of one side that owns the science. There isn't one side whose political ideology, however extreme, is going to be "helped" by the science. You know, when we look at genetics, we see evidence for this incredible human diversity that doesn't fall along these kind of neat stories that people tell about race and I think that information is really powerful for people to know, to kind of blow up some of their own myths about these kinds of things.
Kat: It never has ceased to amaze me that we talk so much in genetics about oh, this disease and this link and this and that. And it's all come from these genome-wide association studies that are 95% or probably 90% now, because it is improving, but from European ancestry populations, when most of the world is not. And yet we try and generalise this information to everybody, even everybody from a different ethnic backgrounds in the same country, but that seems flawed to me.
Paige: It's deeply flawed. Right? And if we think about even what you might think of as quite basic traits, we might think, well, the genetics of skin pigmentation is probably easier to work out than the genetics of intelligence. We see that when researchers actually do studies that capture more of the genetic diversity, especially particularly from African ancestry populations. And they discovered genes related to skin pigmentation that they didn't know about, that we didn't know about, because they didn't have sufficient variation in Northern European populations to even be there to study.
Paige: So if you think about how that's true for skin tone, how much more true is that going to be for anything like a medical disorder or social behavioural disorder? You know, one thing that I think is kind of a blessing in disguise is that when you do a genetic study of educational attainment in predominantly Northern European populations. It's easy for people to look at that and say, well, of course that doesn't generalise. We can't say that we know something about the genetics of the same traits in the broader share of the population. And yes, they're exactly right. And that's also true for medical genetics. That's also true for everything below the neck too. So to some extent, the fact that behavioural genetics focuses people's attention on the problems that are inherent in this lack of representation, of diversity. I think that's a good thing because those problems don't just attend psychological studies, they attend all of our studies.
Kat: I think you used the example in your book, and it's one that I've come back to again, of the chopsticks gene. Where this is sort of the apocryphal story, where they gather loads and loads of genetic data from a load of students in a university and discover a particular genetic variation that associates with using chopsticks. Uh, actually, it's just a genetic variation that's more prevalent in Asian populations and they're the people who use chopsticks. That tells you nothing. That's not the chopsticks gene.
Paige: Exactly. And I think that comes back to, again, this metaphor of the lottery. People have tried to overcome this chopsticks gene problem, technically it's called the problem of population stratification, which is genetic variants differ because of the long arm of human history of demography, of culture, of mating, of the way that societies are stratified within countries and across countries.
Paige: And so there's always this question about if you find a genetic variant, DNA differences correlated with some outcome. Is that because the DNA variant is doing something in your body that through a long chain of events ultimately changes your probability of showing some outcome, or is it just that you've happened to measure a group of people who by virtue of class or geography or culture or history are more likely to experience this outcome for environmental reasons, and also more likely to differ in their distribution of their genetic variance.
Paige: There is no magic bullet to that question. The closest thing we do have, again, is back to this random shuffling of genes between parents as there's this process of genetic inheritance from parents to children. Which is why we're never going to get away without studying family members. No matter how many people we genotype, if we really want to be confident that we're not running into this chopsticks genes problem, we need to be studying, not people who are conventionally un-biologically related, but parents and children and siblings and pedigrees of people in order to be confident about that.
Paige: At the same time, we can't just be doing the way that people with outstanding family members have overcome this problem is if they'll say, okay, well, I'm going to study people who identify as white British, and who are genetically as homogenous with regards to their ancestry as possible. And that, as we know, is both bad for science and it's exclusionary. So the direction of studying more families is one of the things that allows us to be more inclusive in our science. And I think that's really important.
Kat: So if we're coming from a point of view that genetics has at least some influence on life outcomes, exactly how much, we're not sure, but we acknowledge that it's there, then what do we do about it? Because I think, you know, in genetics we, particularly when we're talking about biomedical genetics, the urge to fix. We find the genes and then we fix the genes, we develop drugs or maybe you can do genetic engineering. Or when you start kind of going back to the scary stuff, embryo selection and all these kinds of things. So what do we do with this genetic information? Because it's clear that society is incredibly unequal and that's not just on a genetic level, that's on a deep societal problem level. So how do we use this genetic information and all the society stuff? What do we do about it to actually make people's lives better?
Paige: Yeah. And you know, that is such a huge question. And I will say up front that the book attempts to answer that question from my perspective, which as someone who has a particular set of egalitarian values and political values, how do I see genetics fitting into that? So I think one conversation that I'd like to see more of in the wake of the book is beginning with the premise that you just started here. Which was like, okay, well, we can quibble about how much, but given that it's not zero, how then do we conceptualise equality? What then do we do next with it? And I think that there's going to be competing views on that. So my kind of my personal view is one in which I really have been influenced by Rawls, by Dworkin, by a number of other philosophers who have written more generally about, well, what do we do about the fact that there's luck in people's lives?
Paige: We are used to thinking about this already, when we think about social luck, right? So if we look at children, some are born into well-off stable, happy homes, and some are born into chaotic or abusive or low income homes that are characterised by material deprivation. You know, we look at that and we say, well, that's a source of luck in their lives, right? It's not the child's fault that they were born into this family that had this environment. What do we need to do in order to bring about more equality in those children's ultimate life chances. What do we need to do to make it so that your life is not narrowly gated by the circumstances of your birth? And that's the frame of reference that I want people to bring into our discussion of genetics.
Paige: So if we look and see, okay, genes are related to some extent to how your life goes. A big part of that in the US and UK operates through how genetics influences your success in school, because so many social inequalities are structured by school performance. What do we owe each other regardless of how they fared in either this social or this natural lottery of birth? A really obvious example in the United States is the ways in which we tie healthcare access, just like being able to go to the doctor, being able to have access to medicine. We tie that to employment, which is itself tied to education. And so we've built something that is kind of pinned to the outcome of this genetic lottery in some way, right? We can look at a connection between which genes you happen to be born with and whether or not you're able to go to the doctor when you're sick.
Paige: And I want people to question that, I want people to think about, well, what are the sorts of things that we're comfortable having contingent on the outcome of this genetic lottery and what sort of social goods need to be unhinged from that? Unpinned from that? What sort of things do we owe each other regardless of genotype, regardless of genetically influenced psychological traits in certain ways? And people's answers to that question can differ, but I think that's a different frame than is often brought to bear on our conversations about genetics.
Paige: A lot of times genetics is accused of naturalising inequality. You know, if something's "genetic" there's nothing we can do about it. And there's no use fixing it. And like it's set in stone and that's obviously like total bollocks, right? Like we intervene in genetically influenced traits all the time. If you're wearing eyeglasses you are a living example of that in this exact moment. The fact that something is genetically influenced doesn't mean that it's inexorable or unfixable with social policy. It does mean however that we are currently structuring something such that that outcome is again, pinned to this lottery of birth.
Paige: And I want people to think about, well, maybe we're okay with, for instance, your likelihood of getting a PhD in electrical engineering being related to; you happen to get a certain set of genetic variants that make you very interested in spatial rotation. But we're not comfortable, we don't think it's a good society to the extent that your access to healthcare or your access to libraries or your access to green space is dependent on success in education, success in school.
Paige: So that's the big push that I'm trying to get people away from is instead of thinking of genetics as natural or genetics as inevitable, genetics meaning that this is the only world we can live in. Instead thinking about genetics as a tool for seeing which inequalities between people are currently in our social structures tied to this random shuffling of genotypes. And which one of these do we want them to be tied to that? Which of those chains do we want to break, actually?
Thanks to Paige Harden for chatting with me. Her book, The Genetic Lottery: Why DNA Matters for Social Equality is out now wherever books are sold, including e-book and audio versions, and it’s certainly a thought-provoking read, whether you agree with her or not.
