How Your Family Affects Who You Are & How DNA Affects Your Health
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Then, how did you turn out the way you did? Was it because of your parents, your environment, your siblings? The way I often talk about it is parenting effects are probably overestimated by the general population and sibling effects are probably underestimated because there's just shockingly little research about how siblings affect each other. Also, why trying to appear younger than you are usually fails and how your DNA works and the amazing advances in that field.

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Something You Should Know. Fascinating intel. The world's top experts. And practical advice you can use in your life. Today, Something You Should Know with Mike Carruthers. If you're looking for a job, or the next time you are looking for a job, I have some information that you might find very useful. Hi, and welcome to this episode of Something You Should Know.

When a company is interviewing people for a job on any given day, the fourth person interviewed that day is more likely to get the job. Researchers from Old Dominion University in Virginia analyzed more than 600 30-minute job interviews at a university career center. They found that the fourth person being interviewed got the most attention from hiring managers.

While it's become popular belief that employers often make snap judgments about a potential candidate within the first few seconds of the interview, this study found that decision-makers take closer to five minutes for the first interviewee and reaches closer to eight minutes by the fourth applicant. After this, however, the time hiring managers take to reach a decision begins to decrease with each additional interview.

And that is something you should know. Have you ever sat back and thought to yourself, how did I turn out the way I did? Or how did my kids turn out the way they did? Often people lean on the idea that you turn out the way you do because of how you were parented or because of the family you grew up in.

And then you hear things about birth order, that you are more likely to be a certain way if you're the oldest, or if you're the youngest, or if you're somewhere in the middle. What about all of this? And what about that idea, and we've all noticed this, that multiple kids grow up in the same house with the same parents, yet they all turn out so differently? Well, Susan Dominus has looked at the research on this and uncovered a lot of really interesting findings.

Susan is a writer who has been with the New York Times for several years, and she is author of a book called The Family Dynamic, A Journey into the Mystery of Sibling Success. Hey, Susan, hi, welcome to Something You Should Know.

Thank you so much, Mike. It's a pleasure to be here. So what about all these theories about how people turn out the way they do, how kids turn out the way they do? You know, you'll often hear people say, well, oh, that's because he's the oldest or, oh, he's a middle child. So that that's why that happened.

There are a lot of misconceptions about why kids turn out the way that they do. And some of those misconceptions are about parenting effects. Some of those are about birth order effects.

Families are really messy and complicated things, and it's almost a mythology or an astrology that we impose on our own families to explain why things happen the way that they do when there are many other factors involved that people, I think, underestimate. Well, so we hear things like, for example, you know, firstborns are likely to do this and younger siblings are likely to do that. And is that science or is that just not? Yeah.

Yeah, so it's true. You often hear people saying things like, as if it was just a given fact, they'll say, oh, well, she's, you know, the spoiled one, because she's the youngest, or she is the most conscientious, because she's an oldest sibling. What turns out to be true is that

Probably not that. The best research that has been done on birth order, the biggest studies, the best constructed studies, basically find surprisingly little correlation or no correlation between birth order and personality. So, for example, we tend to think of the oldest child as being the most conscientious in the family.

What we underestimate is the role of developmental psychology and why it feels that way. So let's say there's a 17-year-old in the family. That 17-year-old may well be the most conscientious person in the family. But the 14-year-old little sister, when she gets to be 17 years old, might even be

more conscientious than the 17 year old. Even when you're older, you're going to be more responsible. It's just a kind of developmental quality. So the other thing is that the person who's the most conscientious in their own family might not even be that conscientious relative to the general population. So does birth order determine anything? Or is that just one of those pop psychology things that seems like birth order should matter and it doesn't? Or does it tell us anything?

There's one finding about birth order that is remarkably consistent. The oldest child in a family tends to have a cognitive edge. This is on average, you know, I am the youngest of three, so I need to point out that this is on average, and these effects are not huge, but it's really consistent. And the reasons for that are pretty interesting and maybe even a little bit intuitive.

And when you say they have a cognitive advantage, you mean what? That they're smarter or that they do better in school or academically? Has a little bit of an academic advantage. Okay, so go ahead with, tell me about the cognitive edge that an oldest child has.

The first child is the only child in a family of siblings who ever gets to be the sole focus of their parents' attention. And they get that sole focus at a time that's really developmentally crucial. So they're getting all of the enrichment, all of the attention, all of the eye contact at a time when their synapses are firing like crazy and forming like crazy. And so parents might love all their children equally,

But the second child is always going to have less of their parents' attention than the older child did during that time when that child was an only child. So that's one reason why researchers think that oldest children have this cognitive edge. And by the way, they see this cognitive edge even when that child is only a year old. They do better on tests that they give to babies.

than their younger siblings do when they reach the age of one. So it's really remarkable and it starts really early. However, it increases over time, this gap. And the thinking is that when kids get older, older siblings do a lot of instructing of younger siblings and that there's something that is consolidating of knowledge or is instructive or salient and healthy somehow for cognition in just doing a little bit of that teaching.

So when we talk about, as we started talking about, how a kid turns out, how a person becomes who they are, what can you attribute to that? What does affect how a kid turns out?

When researchers look at twins, let's say they look at fraternal twins, and they try to figure out, okay, well, how much does having a shared environment, being raised in the same home, make them more similar than two people who were raised in different homes? The answer generally is not that much. And as a mother of fraternal twins, I can speak to that. My fraternal twins came out incredibly different. They remained incredibly different.

What does matter about being raised in the same home is whether or not you're going to go to college. That's something that kids raised in the same family tend to have in common. And that's hugely consequential for your income and your income affects so much of who you're likely to be and how you're likely to fare. But in terms of whether you're going to be equally conscientious, whether your kids are going to be equally creative, that's

You know, parents can expose their kids to those things. But whatever they do in the household seems to have much less of an effect than parents really imagine. Well, what about things like morality? I mean, that is something that seems to get passed from parent to child. The values you grow up with seem to stick.

Yeah, I think that, you know, value certainly can be passed down from parents. I think that's what's a little harder to measure are things like personality traits, like how much does parenting make somebody, you know, outgoing or introverted? You know, can parents, you know, these are the kinds of things that we associate, for example, with success, right? Like conscientiousness. Can parents, quote unquote, make their kids more conscientious?

it's unclear. And many researchers would say, probably not. You know, that's not to say that kids come into the world and how conscientious they're going to be is 100% determined by like their genetics. No, how you're going to be, you know, how you're going to turn out is a combination of the sort of genetic nudges that you get from the get-go and the environmental effects that are part of your life. Now,

When we talk about nature and nurture, we think about nature, genetics, and nurture, parenting. But really, it's genes and environment that we're talking about. And parenting is just a small part of the whole picture of the environment.

The environment is the school you go to. It's the neighborhood that you grow up in. It's the, you know, who's your best friend? It's what nature documentary did you watch when you were in fourth grade? It's did you break your leg when you were in second grade? Was your bedroom sunnier than your brother's? The environment is vast. It involves huge amounts of chance.

And it's sort of like you come into the world a certain way, you interact with the environment and all of the random haphazard things that happen to you that changes you a little bit. Now there's a new version of you interacting with every other random element that you come across. Parenting is part of that for sure. It's just a smaller part of it than most people appreciate.

What about major traumatic events that happen to a child? Do those have a disproportionately large influence on a child's development? So there's something known as an adverse childhood event. You know, those are things like abuse or exposure to violence at a very young age or trauma. And we do know that that actually does really change the brain. So if you want to talk about parenting effects, it's probably most common.

profound at the extremes. So like, you know, sort of what people call good enough parenting, you know, parenting that's basically healthy and sane, that's not going to have a huge impact one way or the other on whether your kid is super conscientious or not.

If parents are abusive, they can really do serious damage to their children. Then they can really affect their children's lives. At the other end, I'm not saying that the opposite of abusive is overly involved with your kids' extracurriculars, but if you look at somebody like Richard Williams, right? Like Richard Williams, the father of Serena and Venus Williams, is kind of the other end of the extreme. Like it's not that he's the world's best parent, but in terms of, you know,

getting achievement out of his kids, he was a very unusual parent. He devoted his entire life to making tennis stars out of them. They were very talented to begin with. And if they hadn't been, he wouldn't have been able to do what he did. But most kids, there are probably tons of other young women out there who have the talent that Venus and Serena had, but their parents weren't like these extremes. Their parents weren't willing to chuck everything and devote their lives to tennis around the clock.

Well, I bet a lot of parents who just heard you say about what you said about good enough parenting is like a big relief. It's like, oh, God, thank God, you know, because you always think you could have done better. And but you're saying that that's not having as big an influence on your kid as you think it is.

I think if there's one takeaway, it's that you are not having as big, most parents are not having as big of an influence as they think they are. You know, we agonize over these decisions. Should we have a chore chart? Should we co-sleep? You know, should we let them cry it out? Should we be strict? And, you know, it's at the end of the day, like it's just, it's not as make or break as we think it is. Now, what does matter, I would argue is,

is how your kid feels in the day-to-day moment in your home. Do they feel that you care about them? Do they feel that you are setting appropriate limits? Do they feel safe? Do they feel that you're consistent? So it's not that the parenting decisions that you make are inconsequential for your child's life. Of course they are. It's just that you don't have to feel responsible for whether your kid is valedictorian or not. I would say relieve yourself of a little bit of that pressure.

We're talking about how kids, how people turn out the way they do. Susan Dominus is my guest. She's author of the book, The Family Dynamic, A Journey into the Mystery of Sibling Success.

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So Susan, I'm curious about the effect siblings have on each other, and I'm sure it depends a lot on how close they are. A lot of siblings are far apart in age or don't get along well, so maybe they don't have... So there's probably a lot of variability, but I'm curious because I suspect siblings can have quite an impact.

The way I often talk about it is to say that parenting effects are probably overestimated by the general population because we think it's the be all and end all. And sibling effects are probably underestimated because there's just really not that much. There's just shockingly little research about how siblings affect each other in general. Now, part of that is that siblings are hard to study. There's half siblings, there's step siblings, there's different age gaps among them, there's different gender configurations.

So it has been very challenging to study it effectively, but researchers are starting to find interesting ways to figure out how much do siblings affect each other and how much is just, to the extent that they are similar, how much of that is because of maybe a genetic overlap or because they are being parented the same way. And so there's this one study that I find really fascinating because it gets around those confounds.

What this researcher did was look at school start dates.

We know that kids who go to school a little bit old for their grade, you know, just by virtue of when their birthday falls, those kids, especially I should say in disadvantaged communities, do better academically than kids who are younger. It's just if you're older for your grade, you're going to be a little bit more developmentally advanced. That means you're a little bit easier in the classroom. The teacher likes you a little bit better. Things just go a little bit better for you. And then you have a positive feeling about school. You're more

you know, cognitively mature. So it's, we know that kids who are old for their grade do better. And that's kind of a random element, right? Like, did you happen to be born at the right time for that to be possible? When you look at the younger siblings of those kids, they also do better than would necessarily be anticipated. And that's true regardless of when their birthday is.

So that's how you know that it's having a sibling who had this lucky break that makes the difference for the other sibling who is just not necessarily old for the grade. It's a true sibling spillover effect. It's not parenting that's making it happen, and it's not the genetics. It's just this one random element of did you happen to have a birthday that made the older sibling a little bit older than his or her peers in the classroom.

Is there any research that would show that siblings who are close influence each other more than siblings who are less close? Like, is the relationship of siblings impactful? So what I would say we know is that

In disadvantaged families, the sibling effects tend to be stronger. And one reason for that, it doesn't necessarily speak to whether the siblings are more emotionally close, but they tend to spend more time together because maybe their parents are working long hours or they don't invest as much in extracurricular. So it's not like one kid is out, you know, working.

rock climbing you know all afternoon while the other one is practicing oboe you know the kids are kind of hanging around the house a little bit more when there are fewer resources to spend on extracurriculars so those kids do have more of a of a sibling sibling spillover effect i think when siblings are close and they collaborate they can have this incredible network effect that allows them all to do better than they would if they were into operating independently

But I will also say that sometimes you can see siblings in whom there is this rivalry and that people think that everyone's trying to please their parents. It might have nothing to do with the parents. Sometimes having a sibling who you want to best, perhaps because there is tension there, can be extremely motivating. I mean, this is anecdotal, but in my book, I do write about this family, the Groffs, and

And Lauren Groff is this tremendous novelist, best-selling, award-winning. She has an older brother who she felt always patronized her a little bit. And it created this fury in her to show her worth and show him up, I think, basically. And she told me at one point, and by this, and she was by then like a mother and a very accomplished author. And she said that 90% of what motivated her was this sort of feeling she had towards her brother. I mean, quite an extraordinary thing to say. So...

I think sibling dynamics are complicated. They are messy. They can work in all kinds of different directions. And we're just trying to understand what some of the consistent patterns are. You've talked about how the oldest child often has a cognitive advantage, an academic advantage over the other children. But is there any research that shows that younger children have an advantage somewhere else?

There is good research that finds that younger siblings are overrepresented in elite sports and that they also you look at all the entering freshmen in a class who played varsity sports in high school. More of those kids are younger siblings as well. And the idea is that the oldest kid does well academically and the younger kid says, all right, I'm going to pick a different lane. I know I can excel in this.

Where does the only child fit in this discussion? I'm not aware of any research to suggest that it's like damaging to be an only child. You know, it's true that they lack the kind of network effects that strong sibling groups have with each other.

But they have something else, which is they have all of the, you know, if you think about the oldest child having this academic edge because their parents poured all this enrichment to them, even just for a couple of years. Think about how much that's going to do for an only child over the course of an entire life. Right. Like and it's not just that they have all the parents involved.

attention and enrichment efforts being focused on them, they also have all of the parents' financial resources. And so much of what affects our quality of life, frankly, is, you know, what economic opportunities do we have? After looking at all this research, what other conclusions can you come to?

I mean, I think that consistently I found that when parents know their kids well and they treat them like individuals, you're going to get better results. So it's about setting expectations for your child that are consistent with who your child is. You can't just say, I had one mother say to me, I don't understand. I set really high expectations for both of my children and only one lived up to them. Maybe your second child, you know, is not...

destined to be the valedictorian in the class. Not everybody is. And so when parents set expectations that are inappropriately high for a given child, not only can it be demotivating for that kid, but we also know that it can be linked to high rates of anxiety and depression. What about the idea that parents today are just too involved with their kids and that's not doing them any good?

When I look at these high achieving families, I do see the parents really encouraging their kids to believe that they're tough, to believe they can do it. They let them take risks, even when it was scary. I mean, Marilyn Holifield, who went on to become the first black female partner at a law firm, a major law firm in Florida. She ran an influential boycott. She's just this extraordinary woman.

She was the one who told her parents when she was 15 that she wanted to be one of the first kids to desegregate a high school in Tallahassee. And I'm sure her parents knew it would be awful, but she was hell-bent on doing it because it was the best high school in Tallahassee, and she wanted access to the best high school. And they let her do it, and they never tried to twist her arm into quitting, even when things got really, really tough. I think...

There's language that a cognitive psychologist once used with my family when we were helping one of our kids who was struggling with something. And she said that we just needed to say to him when he didn't want to do something because it made him anxious, hey, you're tougher than you think. You can handle this. And, you know, you're tougher than you think is very much an implied message that I saw in a lot of the families. And that really became extremely useful language for us. I love that.

You're tougher than you think. You're tougher than you think. Yes. And you say it in a very Mary Poppins-like, cheerful and assertive tone without overdoing it. And kids are tougher than they think. Lisa DeMore is a really well-respected child psychologist. She's written several bestselling books. She believes that parents are...

are too afraid of their children's anxiety, and that makes the kids afraid of anxiety. Nervousness, anxiousness, these are normal, healthy responses before you head into a game with a team that you know is going to kick your butt. It is normal to go into a solo at a concert feeling nervous. That's OK. It's not something that means you have to then

avoid altogether so that you don't have that uncomfortable feeling. No, that's a healthy feeling and you're going to survive it. And you know what? If you screw up the solo, you're going to survive that too. It's okay. You're tougher than you think.

Well, this is a topic that I think everyone thinks about, either about themselves, how did I turn out the way I did, or my kids or my siblings, how did we come to be who we are? It's great to get some insight into it. I've been speaking with Susan Dominus. She is a writer who's been at the New York Times for several years, and she is author of a book called The Family Dynamic, A Journey into the Mystery of Sibling Success. There's a link to her book at Amazon in the show notes.

Susan, thank you for being here. Mike, thank you so much. I've really enjoyed talking to you.

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What does it take to lead like a superhero? Well, find out on the Superhero Leadership Podcast, hosted by Marvel's former CEO and legendary turnaround expert, Peter Cuneo. Each week, Peter is joined by top performers from business, media, and beyond, leaders who have mastered the art of impact, resilience, and vision.

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I'm not talking about not perfect in the sense that we make mistakes or make bad choices. I'm talking about biology. So humans have been around for a long time. So one might think that by now, over that time, evolution, survival of the fittest and all that would have weeded out the flaws, the diseases, the genetic imperfections by now. But we have a fairly high rate of genetic diseases compared to other species.

So why aren't we closer to genetic perfection than we are? And will we ever get there? That's what Lawrence Hurst is here to talk about. Lawrence is a professor of evolutionary genetics in the Milner Center for Evolution at the University of Bath. He's author of the book, The Evolution of Imperfection, The Science of Why We Aren't and Can't Be Perfect. Hi, Lawrence. Welcome. Glad to have you on Something You Should Know. Lovely to be here.

So let's begin with an example of what you mean by we're not perfect genetically. One of the things that has been discovered over the last few years, for example, is

is that about half of all fertilized eggs, so the very earliest embryos, half of those will die. In humans? In humans. But if we do exactly the same experiment in fish, for example, the answer's none. They're all fine. So it's a funny human thing. And again, if we look at human pregnancy,

About 5% of human pregnancies will end in a condition called preeclampsia where the mother's blood pressure goes sky high and this can kill the mother and the baby.

So it turns out it's one of the great killers of mothers and babies globally. And the odd thing about this particular condition is it's only seen in humans. So it's a human specific, but lethal condition of pregnancy. And there are many other sort of similar genetical issues where they just leave you scratching your head going, why are we so bad? Did you know, for example, that we've got one of the highest mutation rates? So when

Parents get together to make kids. Usually the kids DNA is a simply a copy of the parents DNA But they we all have new mutations So a little error somewhere in the DNA and we've got one of the highest rates of all species in these errors and one of the consequences of this is that we have a very high rate of So-called genetic diseases or rare genetic diseases. So a rare genetic disease is one that affects less than one in two thousand of us and

But about 5% of us have a rare genetic disease. They're not that rare. And that's because humans are odd. We've got a very high mutation rate. What are some examples of these rare diseases you talk about?

Oh, there's loads of them. Some of the haemophilias, for example, these bleeding conditions, these are quite commonly due to a new mutation in part of the system that makes sure that when you cut yourself, you don't bleed, for example. Haemophilia A, haemophilia B would be some of the more common ones. So that's the sort of thing that we're talking about. They're not common, but you may well have heard of some of them, but they are particularly common in humans.

So when you say mutations, you mean that when two people get together and have a baby, they create this baby, and rather than the baby being just a copy of the genetics from the parents, something changes, right?

Yep, absolutely. You can think of it as a bit like you've got a data file on your computer and you're transferring it over to, I don't know, you're making a copy of it and you're transferring it over to a USB stick. This is a bit like parents copying their DNA, giving it to the kids. What's happening in the process is occasionally mistakes are made.

So just as occasionally that file can end up having not quite the right instructions, or rather not the original instructions you might say, so too when mum and dad make copies of their DNA to give to their kids,

There are differences made because of that copying process. So we're all born with about 50 or so of these new mutations, changes to the DNA. More if your father is old, less if your father is young. Do we know why that happens in humans and why it happens less in other species?

Well, we do indeed. And so this is one of the themes of a body of theory that I think is not particularly well known. It's called the nearly neutral theory. And what it says is that this classical process of natural selection, survival of the fittest, that is not so efficient when populations are small.

And typically what we think natural selection should do is keep the mutation rate really low. Now why is that? Well, it's because organisms are actually well-functioning things. And if I were to give you my lovely watch, for example, and you were just to tinker with it, you're more likely to break my watch and get me very angry. Likewise, if you go to a really well-functioning engine of a car and you just randomly change something, then you're more likely to break the engine of the car.

And the same is true of DNA and mutations. So mutations are like random tinkering of the engine or the Swiss watch. You're more likely to break it. So then the question is, why do we have a rate of mutation that's three orders of magnitude higher than some other things? And that's where this other theory comes in. It says, actually, that selection to keep the mutation rate down is inefficient if populations are small. So our problem is,

in having a high mutation rate is because we evolved when we didn't have a very large number of us. We think there were about 8,000 to 10,000 of us, and evolutionarily speaking, that's a very, very small population. Are there a lot of mutations that get passed down that are fairly benign? And what I mean by that is, as I understand it, some time ago,

There was a mutation and somebody for the very first time was born with blue eyes. And then that person had children who had children who had children who also had blue eyes.

But blue eyes, although it's something that's very obvious, you see it, but it doesn't really have much effect. In other words, being born with blue eyes doesn't change your life a whole lot, doesn't ruin your life, doesn't kill you. It's a mutation, but with no real consequence.

So there are some sort of obvious ones that may well be largely irrelevant in terms of your ability to survive and reproduce and leave kids and so on and so forth. But the great majority of mutations probably have absolutely no effect whatsoever or almost no effect whatsoever. They almost all will have some tiny, tiny, tiny effect, but not one that you can physically see.

That's because most of our DNA appears to be relatively pointless. There's this sort of magical 10% which is not pointless, that if you have an effect in there, you will see some deleterious effect. Probably most of it, yeah, you change it and it has no effect. Do the mutations... So when my parents had me and there were mutations...

Yep, about between 10 and 100 or so. Yep, you are unique. We're all unique. Okay, so when I have children, is it possible for those mutations to stop with me or will I automatically pass them on to my children? You will not necessarily pass them on. So there's two processes we have to think about here. One is what we call purifying selection. So imagine there was a mutation and it killed you. Yes, before you got to reproduce.

That is good old, what we call purifying selection. That mutation came into the population, it killed you, it's gone out again. You will not be transmitting to any kids because you will not have any kids. So that's selection. There's another process which is just simply chance. So you've got two copies of your DNA but the mutation will only have been in one of them. Typically the DNA you get from your dad. We get many more mutations from dad than we do from mum.

But it's quite possible that when you transmit your DNA to your kids, they got your version that you got from your mum and not the version that you got from your dad. So you are giving on the unmutated version.

Just simply the version that you got from mum, not the mutated version that you got from dad. You do get a few mutations from mum, just not as many. So yes, it is possible that you have mutations, you simply don't transmit them, not because they're bad mutations, but simply because in effect they're unlucky mutations. Your kids only have half your DNA, and so...

You flip a coin as it were and half the time you flip the coin and they don't get mutation. Half the time they will get the mutation. Is what you said about large populations and small populations the reason why other animals, flies, mosquitoes, where there's zillions of them, is that why they don't have these problems?

Absolutely, that's why we think this is the case. In the last 10 or so years we've been able to work out what the mutation rate is for lots and lots of different organisms. And we can do this because we can basically work out the DNA of mum, we can work out the DNA of dad, we can work out the DNA of the kids. And then it's a spot the difference competition.

Yeah. So you go, where is the kid's DNA different from mum or dad's DNA? And they'll go, okay, you must have got a new mutation. And so we can work out what's the rate at which that's going on. And the answer is that if you're in a population of mosquitoes, the rate at which that is going on

per unit of DNA is about an order of magnitude lower than the rate at which it's going on in us. But yeah, they've got a lower rate and it turns out that the mutation rate very nicely scales, that we can now know, with how many individuals are there in a population. Lots of individuals in the population and the mutation rate is low. Few individuals in the population and the mutation rate is high.

Well, what's a lot? I mean, we have several billion people on the planet. We have several billion now. We did not have several billion when we evolved. So, as I said, if we go back to before the modern expansion of humans, which is 20,000 years ago or so, we estimate that there were about 8,000 or so of us.

Which isn't many, and that's pretty normal for a primate of our sort of body size. So the other predictor of this is just how big is your body? So whales have a low rate like us. They've got very big bodies and very small population sizes. Likewise, elephants and so on and so forth. So yeah, the things with large-ish bodies, evolutionarily speaking, comparing across all organisms, we've got a large body. So there were historically relatively few of us

And the consequence of that is that when we were evolving, we were much more prone to chance events. So help me understand this, something I've never been clear on. If I got cancer, it might be, or people would say, it could be hereditary, but it could also be a mutation. And a mutation doesn't necessarily bring the disease with it. It creates the disease when it mutates. Is that correct?

Cancer is complex and in many regards what you said is absolutely spot on. So if you look at something like breast cancer, for example, about 5% of breast cancers are highly heritable. So if your mother had breast cancer and her mother had breast cancer, we can now sequencing up your DNA and go, okay, you've got a mutation.

And then you can do what Angela Jolie did, for example, go, "I likely will get breast cancer." And so there you have a key mutation that is really tilting the balance towards you getting cancer. Many other cancers are not like that. There may be weaker genetic predispositions

But many cancers rely simply on bad luck. They're in your body, the cells are dividing all the time, they're mutating all the time, and you could just get unlucky. You may have no predisposition, genetic-wise, towards cancer, but because those cells are dividing all the time, they're mutating all the time, you could just be simply unlucky and develop cancer within your body. And at the moment, because people are living quite long, we estimate that about one in two people will get cancer sometime in their lifetime.

But it isn't necessarily because they inherited genes for cancer. They could have inherited some weaker disposition or they could inherit, as with some of these 5% of breast cancers, very strong predispositions.

And those very strong predispositions are such that you only really need one other mutation and you will get cancer. For the others, you need a handful of mutations, an unlucky combination, and you will get cancer. But yes, you can inherit predispositions to getting cancer, but a lot of cancer is simply bad luck. So how close are we to being able to find mutations and go in there and tinker and fix them?

Great question. So this is really the most exciting age in many regards because what we can now do is sequence DNA

So every one of us has about three billion base pairs of DNA. That's quite a lot in every one of ourselves, actually two copies of that. And we can now work out exactly what that looks like for each and every one of us. And in principle, we can then go and go, okay, you've got this condition, whatever that condition may be, and go, oh, we found what the problem is. You've got this mutation in this gene here.

And we can do that now ultra-fast and ultra-cheap. So let me give you some really, I think, interesting and fantastic figures. So when the human genome was first sequenced, all that DNA from one individual was sequenced, it cost $3 billion. It took about 15 years. We can now do exactly the same for around $100, and it takes an afternoon.

So because of this, you can now go to your doctor and the doctor goes, "I think you've got a genetic condition." Sequence up the DNA. He'll look at it and go, "Right, there we think is the problem."

So there are cases now where, for example, a kid goes into hospital screaming their head off, awful headache, very young kid, and in this case the doctors decided the kid almost certainly had a genetic disease, sequenced the DNA, worked out what the problem is, worked out what the cure was, and that was two and a half days. So this is a revolution in medicine.

In that particular case, it turns out it was a problem with importing a particular vitamin into the cells. It was a B vitamin that couldn't go into the cells, so a diet could fix it. What's particularly exciting at the moment is there's a different sort of fix to these genetic problems, and that different sort of fix is called gene therapy.

So, for example, with haemophilias, but also with sickle cell anemia, which is very common in, for example, the African-American community in America at the moment. But with haemophilias, for example, we know what the mutation is. So you've got a gene, it's making a protein that's not working right, and so your blood isn't clotting properly. You bang your head, you will probably die.

Currently the best we can do is give you synthetic versions or give you blood transfusions. So the idea behind gene therapy is to say no, those are all just sticking plasters. What you really need is the right version of the gene to make the right version of the RNA to make the right version of the protein. And so we can give you the gene and that in a very profound sense is a cure.

But this is a gene that goes into your body to allow you to make the missing protein that allows you to clot your blood properly. It doesn't go to your offspring because it's only going to affect the cells of your body but not the cells of sperm or eggs. And likewise with something like sickle cell anemia, we can take out your bone marrow, engineer the bone marrow genetically by giving it the right gene

putting it back again and you now can be effectively cured of sickle cell disease. It is a cure. You're taking a mutated gene and you're giving the better version of the gene, the one that most other people would have, and that then is working absolutely fine. But there are all sorts of problems with it. It's not a pleasant process to have this done and there is mortality along the route.

So the first gene therapy trials had to be stopped, for example, because it turned out that the intervention itself was causing downstream problems, was actually causing cancer. Some of the next ones had to be stopped because the way of delivering the gene, it turns out, caused a massive immune response in the poor individual concerned and they died. So it's been a very slow birth, but we think we're overcoming a lot of these technical hurdles and most particularly safety hurdles.

And so I suspect it's something that we will hear a lot more about in the not too distant future. Well, I suspect everyone has wondered, you know, why do we have cancer and other genetic illnesses? And why can't we get rid of them? And I appreciate the explanation. And it sounds like anyway, that there is promising future in medicine that will address this whole issue.

I've been speaking with Lawrence Hurst. He is a professor of evolutionary genetics and author of the book, The Evolution of Imperfection, The Science of Why We Aren't and Can't Be Perfect. And there's a link to his book in the show notes. Thank you, Professor. I appreciate the explanation. Thank you very much. It's been a real pleasure. Thank you.

Your kitchen has a way of attracting clutter that you probably don't even notice. So the editors at Delish.com have some advice to get rid of the clutter. Starting with a really easy one, the real estate agent and pizza delivery magnets on the fridge. They can go. Then there's your plastic container collection.

Empty food storage containers take up a lot of space in the kitchen. The recommendation is to limit yourself to two sizes of reusable containers, five to six pieces in each size. And that way you're not fighting to find the right lid for each bowl. Coffee mugs. They just seem to multiply and pile up. Most people don't need more than six coffee mugs. The rest can go.

Anything that came for free with your dinner. Spare chopsticks, soy sauce packets, kids' meal toys. You're always going to get more the next time you order, so there is no point in stockpiling.

barely used cookbooks. If you've owned a cookbook for over a year and haven't made a single thing from it, it's probably time to consider selling it. Unless it's a family heirloom, in which case you could just move it to the living room. Pots, pans, or skillets. There's a pretty good chance if you look where you keep your pots and pans and skillets and things, there's a few in there that you never use. I can't remember the last time you used it. So why do you keep it?

Those recipes you're saving for someday. If you printed out or tore out of a magazine a recipe more than a month ago and you haven't made it yet, you're not going to make it. So you might as well just get rid of them. And that's okay. And that is something you should know.

A great way to show your support for this podcast is to leave a rating and review on whatever platform you listen on, Apple Podcasts, Spotify. Most all of them have a way to leave a rating and review, and they help us, and we appreciate it. I'm Mike Carruthers. Thanks for listening today to Something You Should Know.

I'm Amy Nicholson, the film critic for the LA Times. And I'm Paul Scheer, an actor, writer, and director. You might know me from The League, Veep, or my non-eligible for Academy Award role in Twisters. We love movies, and we come at them from different perspectives. Yeah, like Amy thinks that, you know, Joe Pesci was miscast in Goodfellas, and I don't. He's too old. Let's not forget that Paul thinks that Dude 2 is overrated. It is. Anyway...

Despite this, we come together to host Unspooled, a podcast where we talk about good movies, critical hits, fan favorites, must-sees, and in case you missed them. We're talking Parasite the Home Alone. From Grease to the Dark Knight. We've done deep dives on popcorn flicks. We've talked about why Independence Day deserves a second look. And we've talked about horror movies, some that you've never even heard of like Ganja and Hess. So if you love movies like we do, come along on our cinematic adventure. Listen to Unspooled wherever you get your podcasts. And don't forget to hit the follow button.

You might think you know fairy tales, and you might think that they are cute and sweet and boring. But the real grim fairy tales were not cute at all. They were very dark, and they were often very grim. On Grim Grimmer Grimmest, we tell a grim fairy tale to a bunch of kids.

Perfect for car rides or screen-free entertainment, Grim Grimmer Grimmest activates kids' imaginations and instigates fun conversations because fairy tales speak to all of us at a very deep, primal level, and they raise interesting topics and questions that are worth chewing over together as a family.

Every episode is rated Grim, Grimmer, or Grimmest. So you, your kids, your whole family can choose what is the right level of grim for you. Though if you're listening with grandma, she's just gonna go for Grimmest. Trust me on this one. Tune in to Grim, Grimmer, Grimmest and our new season available now.