Speaker 1: Hey, welcome to Sign Stuff, a production of iHeartRadio Horhea
Speaker 1: Cham and today we are tackling the science of baldness.
Speaker 1: Going bald is something that happens to a lot of people.
Speaker 1: But why do we go bald? Who goes bald? And
Speaker 1: why does it affect us so much? I'm going to
Speaker 1: be reviewing the most current theories about the origins of baldness,
Speaker 1: and I'm going to talk to a couple of experts
Speaker 1: on two related questions. Why is there a negative stigma
Speaker 1: about baldness and is baldness really hereditary? In both cases,
Speaker 1: I think the answer will surprise you, so comb over
Speaker 1: with us as we uncover the hairy truth about the
Speaker 1: science of baldness. Enjoy. Hey, everyone, here are some interesting
Speaker 1: facts about baldness. According to a recent paper in the
Speaker 1: prestigious journal Nature Reviews, about fifty percent of men and
Speaker 1: twenty five percent of women experience some form of balding
Speaker 1: or hair loss by the time they're fifty years old.
Speaker 1: This translates to roughly fifty million men and about thirty
Speaker 1: million women in the US alone. It also varies a
Speaker 1: lot with ancestry or race. If you're of South Asian descent,
Speaker 1: like from India or Pakistan, your chances of losing hair
Speaker 1: by the time you're fifty jumps to fifty eight percent,
Speaker 1: whereas if you're of East Asian descent, like from China
Speaker 1: or Korea, the number drops to twenty five percent. It
Speaker 1: also depends a lot on your age. For example, if
Speaker 1: you're of East Asian descent, your chances of losing hair
Speaker 1: in your twenties is small, only about two point three percent.
Speaker 1: In your thirty s it's four percent. In your forties
Speaker 1: it's eleven percent, although way up to forty seven percent
Speaker 1: by the time you reach seventy. There are several types
Speaker 1: of baldness for men and women. If names like M
Speaker 1: one or C two, or YOU three or type three,
Speaker 1: depending on the pattern of hair loss that you get,
Speaker 1: whether it starts in your forehead or the corners or
Speaker 1: the top of your scalp. Now, when I started this episode,
Speaker 1: I wanted to answer the question why do we go bald?
Speaker 1: But I quickly found out the answer is, we don't know.
Speaker 1: From an evolutionary perspective, we don't know why this is
Speaker 1: involved in humans. It's sort of related to your age.
Speaker 1: So evolutionary biologists have proposed theories with that in mind.
Speaker 1: For example, one theory says that it may be assigned
Speaker 1: to the rest of your tribe that you're older and
Speaker 1: therefore more mature and wiser, and therefore you should have
Speaker 1: a position of dominance or leadership. But there are also
Speaker 1: theories that say that it's as signed to others that
Speaker 1: you're old and therefore not very good material. Both theories
Speaker 1: but explain why baldness helps your species survive. We also
Speaker 1: don't quite know why baldness happens at the level of
Speaker 1: hair follicles. We know that when people experience androgenetic alopecia,
Speaker 1: which is the scientific name for male and female pattern
Speaker 1: hair loss, the hair follicles in your scalp shrink and
Speaker 1: become the kind of follicles that cover the non hairy
Speaker 1: parts of your body, But we don't really know why
Speaker 1: this happens. Our current best theory is that it's kind
Speaker 1: of the opposite of when young men start to grow
Speaker 1: a beard during puberty. At some point, your hair follicles
Speaker 1: are just preprogrammed to be more sensitive to your hormones
Speaker 1: and change from one kind of hair to another. So
Speaker 1: when you're a teenager, the hairs on your armpits pubic
Speaker 1: areas and your chin and upper lip for men, turn
Speaker 1: into the kind of thick and hairy kind of hair,
Speaker 1: and at some point, when you get older the hair
Speaker 1: is on your head do the opposite and turn into
Speaker 1: the thin, wispy kind. There are hormones that scientists think
Speaker 1: are involved, like testosterone or diehydrotest ptosterone or DHT, and
Speaker 1: enzymes that contribute to this, like five alpha reductase type
Speaker 1: one and two. We can see that these molecules are
Speaker 1: more active involving hair follicles, but what sets this process
Speaker 1: in motion for what is actually happening at the cellular
Speaker 1: and molecular level is not quite clear. Now, there are
Speaker 1: some cool things we do know about the genetics of baldness.
Speaker 1: I'll get to that later in the program with a
Speaker 1: scientist who's done one of the largest ever genetic population
Speaker 1: studies on baldness. But first, there was one section in
Speaker 1: this Nature Journal paper that caught my attention, and that
Speaker 1: is a section about how baldness impacts your quality of life.
Speaker 1: The scientists right, quote androgenetic alopecia can trigger profound negative
Speaker 1: psychological effects in affected individuals, owing to social pressure to
Speaker 1: maintain quote good hair end quote. In other words, the
Speaker 1: only negative effective bondness are psychological. So to get to
Speaker 1: the bottom of this, I reached out to a psychologist
Speaker 1: who's made it his mission to debunk this negative stigma
Speaker 1: that bondness has in our society and to teach people
Speaker 1: that bondness, no pun intended, is all in our heads. Well,
Speaker 1: thank you, doctor Jenkowski for joining us pleasure. Can you
Speaker 1: please tell us who you are and what do you do?
Speaker 2: Yes, I'm doctor Glennankovski. I am a associate professor University
Speaker 2: College Dublin, and I'm a researcher in psychology who specializes
Speaker 2: in the social and cultural interpretation of alopecia.
Speaker 1: And is that the term we should be using for
Speaker 1: bondness or are ukay we say bondness or.
Speaker 2: Yeah, I'm much more for a further term, boldness as well.
Speaker 2: I tend to use alopecia in the Ireland because my
Speaker 2: accent and a lot of Irish people think I'm saying
Speaker 2: bravery rather than boldness.
Speaker 1: Is that true?
Speaker 2: Yeah? I say boldness like being bold. Oh, I see,
Speaker 2: and it's happened so many times now an island that
Speaker 2: I really I've switched a bit.
Speaker 1: Well, there might be another interesting topic for you to
Speaker 1: research boldness. Yeah, and whether it's related to baldness.
Speaker 3: Yes, but you've done a lot.
Speaker 1: Of research on this stigma against baldness. Can you tell
Speaker 1: us what that stigma is?
Speaker 2: So there is a tendency for people to have attitudes
Speaker 2: that are stigmatizing towards men and their boldness in particular.
Speaker 2: Typically there's experimental studies that show that people hold more
Speaker 2: negative attitudes towards men with boldness than they do men
Speaker 2: with full heads of hair.
Speaker 1: Okay, can you describe these studies a little bit.
Speaker 2: It is actually a large evidence space. So the majority
Speaker 2: of studies actually tend to be experiments where a group
Speaker 2: of people are divided randomly into two conditions and presented
Speaker 2: images of the same man airbrushed, typically with a full
Speaker 2: head of hair, and then with some boldness. And so
Speaker 2: it's that say, mimbiture of the man, same facial features, etc.
Speaker 2: And they are asked to rate the image of the
Speaker 2: man on certain characteristics like how masculine, how successful, etcetera.
Speaker 1: And there's a bias towards certain attributes there.
Speaker 2: Is, Yeah, and those tend to be that those men
Speaker 2: are less attractive, older, that they may be less dominant
Speaker 2: and some other negative characteristics.
Speaker 1: So there is a negative bias that people have about
Speaker 1: bald men. But here's the thing about those studies. According
Speaker 1: to doctor Jenkowski, A, people also have a positive bias
Speaker 1: towards bald men in some categories, and b these negative
Speaker 1: and positive biases are not that big.
Speaker 2: The re such does show that, and I don't mean
Speaker 2: to minimize it. However, I do question how totalizing that
Speaker 2: stigma is because there are also some positive attributes that
Speaker 2: people make about bold men, like that they're more inclined
Speaker 2: to be leaders, or that they're more affablen approachable than
Speaker 2: haired men. And then sometimes these differences are also quite small.
Speaker 2: People can exaggerate how bigly are, especially journalists or businesses,
Speaker 2: but actually if you look at their data, they're quite small.
Speaker 1: New characterized how small they are.
Speaker 2: Yeah. So one study found that out of a scale
Speaker 2: of one hundred of attractiveness, bold men were seven percent
Speaker 2: less attractive than their head counterpouts and rated on average
Speaker 2: about two years older than the head counterpart images. So
Speaker 2: two years older, seven cent less out of one hundred.
Speaker 2: It's not a huge amount.
Speaker 1: No, it's not. I would have thought it was higher,
Speaker 1: but that seems are most negligible.
Speaker 2: I would have thought that too if I wasn't a
Speaker 2: researcher studying this. Most people think this too, because most
Speaker 2: of us are influenced by advertising and marketing of anti
Speaker 2: bold products.
Speaker 1: And this brings up the question where does this negative
Speaker 1: stigma against bog people, or at least the impression that
Speaker 1: is a big negative stigma against boldners come from. And
Speaker 1: here doctor Tinkowski has a s pricing theory.
Speaker 2: It really does come from anti boldness businesses. They are
Speaker 2: the ones who profit from this stigma. And we've had
Speaker 2: a long history of it, and it's ramped up since
Speaker 2: the nineteen eighties when anti bold products for the first
Speaker 2: time in history, got more official approval.
Speaker 1: Wow, so you're looking it to the business of selling
Speaker 1: anti partners treatments. It's sort of a timing issue.
Speaker 2: Well, we've always had boldness since men have been around.
Speaker 2: But what we can see in the historical record is
Speaker 2: that there were many neutral interpretations of boldness. There were
Speaker 2: some negative and there were also some very positive interpretations.
Speaker 2: When we see the rise of snake oil products in
Speaker 2: the eighteen hundreds and the nineteen hundreds, some of them
Speaker 2: were for hairy growth. Of course, they weren't effective, but
Speaker 2: their marketing was designed to show that old men needed
Speaker 2: these products, needed these treatments for this devastagencies, and if
Speaker 2: they didn't take it, they might not get a job,
Speaker 2: they might not get a date, they might not be happy.
Speaker 2: When they became approved in the eighties and onwards, that
Speaker 2: gave them scientific legitimacy these products so that doctors and
Speaker 2: professionals could start to say, these are treatments I see.
Speaker 1: Whereas before you might tell your doctor, oh, I think
Speaker 1: I'm losing my hair, and the doctor might be like, yeah,
Speaker 1: it's normal, no big deal, nothing's going to happen to you.
Speaker 1: Now they might be like, oh, there's a treatment for that.
Speaker 2: Exactly. Those pharmaceutical companies have done training videos, they've done
Speaker 2: training programs, They've targeted medical professionals and doctors to convince
Speaker 2: them that bolding men and bolding people in general need
Speaker 2: these treatments.
Speaker 1: Now, it's hard to say how much of a role
Speaker 1: the pharmaceutical and Bontner's treatment industries have had in creating
Speaker 1: this negative stigma against baldness. As I mentioned, there are
Speaker 1: theories that tie it to our evolutionary history, but it's
Speaker 1: also hard to discount. For example, remember the Nature Journal
Speaker 1: paper I've been citing. That paper was written by nine scientists,
Speaker 1: all of whom have positions at major universities, but at
Speaker 1: the end of the paper, the journal requires them to
Speaker 1: disclose any conflicts of interest. So here's the list of
Speaker 1: those conflicts of interest for that paper. Authors one two
Speaker 1: are inventors on patent applications related to hair loss treatment
Speaker 1: filed by the University of California, Irvine. Author two is
Speaker 1: co founder and chief scientific officer at a corporation and
Speaker 1: has received consultation fees from Audit Labs and lorel Author
Speaker 1: three has received consultation fees from DS Laboratories, Almirale, thirty Madison,
Speaker 1: Eli Lilly and Company, Peiser, Iovan Sciences, Bristol Meyers, quibb
Speaker 1: Ortho Dermatologics, and Sun Pharmaceutical. Author four has received consultation
Speaker 1: fees from Eli Lilly and Company, peiser Olaplex, and Maovn Sciences,
Speaker 1: and they direct the Ethnic Skin program at John Hoppins University,
Speaker 1: funded by an educational brand from Jansen. Author five has
Speaker 1: received salary payments from Life and Brain GNBH. Author six
Speaker 1: has received clinical trial funds from Eli Lilly, and company.
Speaker 1: Author seven has received consultation frees from Eli Lillyan Company
Speaker 1: and has received clinical study funds from Eli Lillien Company, Pfizer,
Speaker 1: and ATB. Authors eight and nine declare no competing interests. Yeah,
Speaker 1: that's a lot of conflicts of interest.
Speaker 3: All right.
Speaker 1: When we come back, we're gonna talk about whether the
Speaker 1: treatments all these companies are pushing actually work. Do they
Speaker 1: stop baldness or is it all snake oil. Stay with us,
Speaker 1: we'll be right back. Welcome back. We're talking about the
Speaker 1: size of baldness, and so we've talked about what we
Speaker 1: know and don't know about what causes baldness. Now we're
Speaker 1: going to talk about the treatments that are out there
Speaker 1: for hair loss. In terms of medicines, there's one called monoxidyl,
Speaker 1: which was originally made to treat hypertension, but then women
Speaker 1: patients started reporting extra hair growth and so it became
Speaker 1: a baldanis medicine that you put on the scalp. Scientists
Speaker 1: have some ideas about what this medicine actually does, but
Speaker 1: not really. Another class of treatments are five alpha reductase inhibitors,
Speaker 1: which includes the popular drug called finasteride. Scientists know these
Speaker 1: treatments block the enzyme that splits the stosterone called five
Speaker 1: alpha reductas, but they don't know much beyond that. Now,
Speaker 1: do these treatments actually work a sort of, according to
Speaker 1: doctor Jenkowski.
Speaker 2: So there are metro analyzes. These are series of studies
Speaker 2: that look at large pools of data of menking these
Speaker 2: products versus men who don't take these products, and they're
Speaker 2: more objective. So these matronalyses have looked many anti baldness
Speaker 2: products and what they've found is that most produced between
Speaker 2: eight to twelve hair follow calls in a centimeter squared
Speaker 2: area of scalp that's monitored, and that's some hairy growth.
Speaker 2: It's not nothing, but on average most people have one
Speaker 2: hundred and twenty hair follow calls and that's centimeter squared
Speaker 2: area of regrowth.
Speaker 1: What doctor Jenkowski seeing is that these treatments do help
Speaker 1: you grow back on average about eight to ten percent
Speaker 1: of the hair you lose, which is not nothing, but
Speaker 1: it's also not a lot.
Speaker 2: So most people do not find that to be a
Speaker 2: cosmetically meaningful amount of hair regrowth. I see these products
Speaker 2: might be better at preventing further boldness. It's a bit hard
Speaker 2: to determine that, but in terms of actual hair regrowth
Speaker 2: is quite minimal.
Speaker 1: And of course you have to weigh that against the
Speaker 1: potential side effects of these treatments.
Speaker 2: And obviously the bigger issues which the Metro analyses to
Speaker 2: show as well, is that some of these products do
Speaker 2: risk quite severe side of x. You know, if you're
Speaker 2: taking finasteride, for example, this is a common antibodleness product.
Speaker 2: Typically it's taken orally and it disrupts your hormonal system,
Speaker 2: that's how it's working. But there's evidence so it's affecting
Speaker 2: all sorts of other things that are really important to
Speaker 2: your bodily functions, like your mood. Men who've taken a
Speaker 2: finanasteroid of reported vision problems, reported mood issues, sexual dysfunction issues,
Speaker 2: these hosts of side effects.
Speaker 1: For finasteride fills. The US Food and Drug Administration or FDA,
Speaker 1: has issued a warning that there is a risk of
Speaker 1: depression in suicide ideation when using this drug, and according
Speaker 1: to the Nature paper, there's also a risk of impotence
Speaker 1: after you start taking the drug.
Speaker 2: And what's really difficult for men taking finasteride is you
Speaker 2: don't which kind of man you're going to be. The
Speaker 2: one that's going to be negatively somewhat permanently affected by
Speaker 2: these side effects, or the ones that might have safe
Speaker 2: experience of it.
Speaker 1: Wow, in which case, maybe it's not worth it for
Speaker 1: those extra eight twelve pollicles exactly. There's also the possibility
Speaker 1: of hair transplants, which is where they take follicles from
Speaker 1: one part of your scalp and implant them in the
Speaker 1: areas where you're losing hair. This treatment is expensive and
Speaker 1: it's not for everyone. It sort of only works for
Speaker 1: thinning hair, not full hair loss. So now my question
Speaker 1: was is this all worth it? What's really the impact
Speaker 1: that baldness has in people's lives? Is there any data
Speaker 1: as to how baldness affects you in life, or in
Speaker 1: your profession or in your social life?
Speaker 2: There is, yeah, Bolting men are surveyed about discrimination romantically
Speaker 2: and employment socially. What's difficult is that most of these
Speaker 2: studies are commercially funded and biased, and some of the
Speaker 2: studies are very very poor, So it might just be
Speaker 2: a market research a series of questions that are really leading,
Speaker 2: that are kind of pishing men to suggest they're discriminated
Speaker 2: against when they're not. Those surveys do show that some
Speaker 2: men report some discrimination and many men do not report any.
Speaker 2: A really important study by Goslin and colleagues in their
Speaker 2: eighties asked bolding men and haired men what they expected
Speaker 2: boldness discrimination to be, and then what the actual reality
Speaker 2: of old discrimination was, and in all cases the reality
Speaker 2: was much easier than bold men and haired men predict it.
Speaker 2: So I think those are really useful to put it
Speaker 2: into perspective for bolding men. We get told that there's
Speaker 2: huge amounts of discrimination, but actually the reality is that
Speaker 2: really it's quite rare.
Speaker 1: What effect do you think this negative stigma and this commercialization,
Speaker 1: what does it have on men and people who might
Speaker 1: be dealing with boldness.
Speaker 2: You know, there's a word called medicalization, and it's this
Speaker 2: term for how normal aspects of our bodies are often
Speaker 2: changed into diseases, sometimes for commercial profit, and it really
Speaker 2: changes how we respond to those aspects of our bodies
Speaker 2: and how we view them. Bold men increasingly see their
Speaker 2: boldness as a devastating, disadvantageous disease. It's real shame because
Speaker 2: if you look properly at history and you see so
Speaker 2: many bolding men of the norm, and that many many
Speaker 2: accept it, and that also find positives from it. Shakespeare,
Speaker 2: for example, said boldness gives you wits. You don't have
Speaker 2: to listen to the political opinions of barbers. Shakespeare said,
Speaker 2: there are all these lovely little advantages from it as well.
Speaker 2: So it's a little bit about having a healthier perspective
Speaker 2: about it. The loveliest thing for me is that many
Speaker 2: bold men report a healthier perspective from it, including feeling
Speaker 2: less superficial about their own appearance. You know, they accept
Speaker 2: their bodies and that's great because all of us age
Speaker 2: and all of our bodies change in different ways and
Speaker 2: that shouldn't be feared. But also they don't look at
Speaker 2: other people so superficially. They can also see past appearance,
Speaker 2: and that's a beautiful thing in a vain world.
Speaker 1: Yeah, oh that's interesting. It can change how you see others. Yeah,
Speaker 1: it is beautiful. It can also help you see.
Speaker 2: Beauty, real beauty, which is inner beauty, which is making
Speaker 2: someone laugh or you know, acts of kindness. It's that
Speaker 2: kind of beauty that you know, sustains a long term
Speaker 2: relationship as well. If we're judging people on their head
Speaker 2: hair follow calls, I don't think that makes a good marriage.
Speaker 2: I think a good marriage is you know most people
Speaker 2: realize is beyond the surface.
Speaker 1: All right, we talked about the word when and why
Speaker 1: of boldness. Now we're going to talk about the who
Speaker 1: who ends up losing their hair is a genetic and
Speaker 1: if it is, is it something we can predict When
Speaker 1: we come back, We're going to talk to each geneticis,
Speaker 1: especially in appearance traits, and who was involved in creating
Speaker 1: one of the largest and most comprehensive genetic population models,
Speaker 1: that is the world's or most expert in predicting who
Speaker 1: will go bald. We'll see what it says about me.
Speaker 1: So stay with us and we'll be right back. Hey,
Speaker 1: welcome back. We're now going to talk to Professor Manfred Kaiser,
Speaker 1: a molecular biologist at Erasmus University in the Netherlands who
Speaker 1: specializes in the genetics of appearances. Now this is pretty cool.
Speaker 1: Imagine that you're at a crime scene and you find
Speaker 1: some DNA of the person you think might have committed
Speaker 1: to crime. What if you could take that DNA and
Speaker 1: from that genetic code you could tell if the person
Speaker 1: was tall, or had dark hair or blue eyes, or
Speaker 1: had a small nose, or was bald or what if
Speaker 1: you found the DNA of a famous historical person like
Speaker 1: Genghis Khan or Cleopatra, or the DNA of a distant
Speaker 1: human ancestor, could you tell from their DNA what they
Speaker 1: looked like. That is the dream of doctor Kaiser and
Speaker 1: his colleagues, and to test his idea, they decided to
Speaker 1: start with baldness. In twenty twenty two, they published the
Speaker 1: results of one of the largest genetic population studies ever
Speaker 1: done on baldness, where they looked at the DNA and
Speaker 1: the hairline of one hundred and eighty six thousand men
Speaker 1: of European descent, and then they looked at whether the
Speaker 1: resulting data could predict who was going to go bald
Speaker 1: or not. To tell us about what they found, here
Speaker 1: is Professor Manfred Kaiser. Well, thank you doctor Kaiser for
Speaker 1: joining us.
Speaker 3: Well, you're welcome.
Speaker 1: You recently posted the paper on the genetic markers of baldness.
Speaker 2: Yeah.
Speaker 3: So, baldness, of course is a very remarkable visible trade,
Speaker 3: especially in men. So we were interested in looking into
Speaker 3: the predictability. So people do what they call genome white
Speaker 3: association studies, so they basically scan the genome of one
Speaker 3: thousands and tens of thousands and hundreds of thousands of
Speaker 3: which they know, for instance, may it pad on baldness.
Speaker 3: So you need these two types of information, and then
Speaker 3: they ask is there one site in the human genome
Speaker 3: that is more frequent in people with baldness.
Speaker 1: In other words, doctor Kaiser and his team had access
Speaker 1: to the DNA of one hundred and eighty six thousand
Speaker 1: men in Europe, for which they knew if they had
Speaker 1: baldness or not. Then they asked that there was one
Speaker 1: gene that could predict whether a man was going to
Speaker 1: be bald or not. And they found two things that
Speaker 1: are surprising. The first is that there isn't a gene
Speaker 1: that is going to make you bald. There's hundreds of them.
Speaker 3: For male pattern baldness. It seems to be hundreds of genes.
Speaker 3: All these different genes work together and make what we
Speaker 3: actually see in the end as made pattern baldness.
Speaker 1: Yes, it's not just one gene that makes you go bald,
Speaker 1: it's hundreds of genes. Wow, so many genes. Why are
Speaker 1: there so many genes involved in something like hair loss.
Speaker 3: Yeah, that's a good question. That's a good question. You
Speaker 3: have to ask evolution why they made it so complicated. Apparently.
Speaker 3: You think, oh, so the hair falls out, that is simple,
Speaker 3: But the reason why a hair may fall out is
Speaker 3: not simple at all. And of course these genes, they
Speaker 3: all play different roles in molacular pathways that exist, and
Speaker 3: that makes the complexity.
Speaker 1: I see. It's not a simple process, even though the
Speaker 1: end result is relatively simple. Indeed, yeah, baldness is complicated.
Speaker 1: You might have heard that male pattern baldness was due
Speaker 1: to one gene that is passed down from your mother's
Speaker 1: side of the family, but this is not quite true.
Speaker 1: When you look at the genome of hundreds of thousands
Speaker 1: of men, you see that there are hundreds of genes
Speaker 1: that influence the end result of losing your hair. There
Speaker 1: is one gene in particular that does come from your
Speaker 1: X chromosome, which is passed down from your mother, that
Speaker 1: has a higher influence than others, but it's not higher
Speaker 1: by a lot, according to doctor Kaiser, and there are
Speaker 1: still hundreds of other genes involved. And doctor Kaiser says
Speaker 1: this is not unusual. In the human body. Any single
Speaker 1: thing about the way you look is determined by many
Speaker 1: many genes. Your height, your skin color, the shape of
Speaker 1: your face or nose, whether you have curly or straight hair,
Speaker 1: studies have found that those are also determined by many
Speaker 1: many genes. According to doctor Kaiser, there's only one appearance
Speaker 1: trade that scientists have found is the by a single gene.
Speaker 3: So red hair is the only human appearance trait which
Speaker 3: is actually monogenic, one gene, one trade, but all other
Speaker 3: appearance traits are influenced by a large number of genes.
Speaker 1: That's right, there's a single gene for red hair. If
Speaker 1: you have it, your hair is red. If you don't
Speaker 1: have it, your hair is not red. But that's the
Speaker 1: only gene related to how you look. That's like that.
Speaker 3: Well, people thought in the past. Eye color is simple.
Speaker 3: I mean, there is the notion that brown eye is dominant,
Speaker 3: and in many cases, if you have one brown eye parent,
Speaker 3: the child is brown. But not in all cases. And
Speaker 3: this is not because the father is not the father.
Speaker 3: This is actually because eye color does have many more
Speaker 3: than one or two genes. We actually found more than
Speaker 3: fifty genes for eye color, but there is indeed one
Speaker 3: or two that have a larger effect. And therefore, in
Speaker 3: many situations, if you have one brown eyed parents, you
Speaker 3: have a brown eyed child, but not in all cases.
Speaker 1: All right. The second surprising thing that doctor Kaiser and
Speaker 1: his colleagues learned about the genetics of bondness was when
Speaker 1: they tried to use the one hundred genes they found
Speaker 1: to predict who is going to go bald and who
Speaker 1: is not. And when you do that, you find that
Speaker 1: you can't.
Speaker 3: And we have done this prediction and tens of thousands
Speaker 3: of people. Yeah, so it's large data set. So in
Speaker 3: a prediction studies, people use a term that includes sensitivity
Speaker 3: and specificity, and you don't have to understand what that
Speaker 3: term is. You only have to know that this term
Speaker 3: runs between point five and one. So what we see
Speaker 3: with these different categories of maypattern baldness is that they
Speaker 3: run between say point seven and maybe point seventy five.
Speaker 3: So it's somewhere in the middle between random prediction and
Speaker 3: accurate prediction.
Speaker 1: What doctor Kaiser is saying is that even if you
Speaker 1: take these one hundred genes into accounts that we know
Speaker 1: are associated with baldness, you still can't accurately predict who's
Speaker 1: going to go bald. Your prediction falls somewhere between a
Speaker 1: random guess and always being right. So what does that
Speaker 1: tell you? So it tells you that they predict something,
Speaker 1: but this is far away from accurate prediction, which also
Speaker 1: tells you that these hundreds are not enough, and that
Speaker 1: tells that people have to find more genes. Doctor Kaiser
Speaker 1: thinks there may be more than a thousand genes that
Speaker 1: determine whether you will go bald or not, and to
Speaker 1: find out what they are we need more data because
Speaker 1: that difference in accuracy might be hidden in genes that
Speaker 1: have a low effect on hair loss, which means they
Speaker 1: are hard to find. Okay, you might be wondering, for hey,
Speaker 1: what if hair loss is not one hundred percent genetic,
Speaker 1: wouldn't that explain why it's so hard to predict? And
Speaker 1: that is true. There may be some environmental components to baldness,
Speaker 1: but doctor Kusler says scientists are pretty sure baldness is
Speaker 1: mostly genetic, and we know this from twin studies. Scientists
Speaker 1: attract identical twins separated at birth and compare them to
Speaker 1: twins that grew up together. For the most part, if
Speaker 1: you're twin who has the same DNA you do is bald,
Speaker 1: there is a pretty good chance you are bald too. Okay,
Speaker 1: so what does this all mean and specifically, what does
Speaker 1: this all mean for my hair. Okay, so I'm training
Speaker 1: fifty this.
Speaker 3: Year, but you know that's quite good in terms of bolts,
Speaker 3: I cannot see.
Speaker 1: Thank you. So far, so good. So my father still
Speaker 1: has all his hair. And on my mother's side my grandfather,
Speaker 1: her father was bald. Oh, and some of my mother's
Speaker 1: brothers are bald, but some are not. So what does
Speaker 1: that mean for me? Do you think?
Speaker 3: Well? Not so easy indeed. But obviously this one gene
Speaker 3: that comes from your mother's side, that's only one of
Speaker 3: one hundreds of thousands, so that per se doesn't tell
Speaker 3: you much. So if they're fifty percent from your father,
Speaker 3: give you all the non bold then of course the
Speaker 3: sum of all the others is larger than the effect
Speaker 3: of this one gene on the X chromolome. So maybe
Speaker 3: you will not develop it.
Speaker 1: At least that's the hope.
Speaker 3: If you would do the genetic tests, you would come
Speaker 3: up with a fairly low probability.
Speaker 1: Okay, I guess my hair loss is TBD to be
Speaker 1: determined or is it to bald determined. We'll have to
Speaker 1: check in in a few years to see how good
Speaker 1: this prediction was. But doctor Casher thinks there's maybe a
Speaker 1: more important question to ask here.
Speaker 3: So the question is why are you doing this? Why
Speaker 3: do you want to know?
Speaker 1: In other words, if someone could predict whether you were
Speaker 1: going to go bald or not, what are you going
Speaker 1: to do with that information? We now know it's not
Speaker 1: going to be possible to perfectly predict baldness. I mean
Speaker 1: not even red hair can be predicted with one hundred
Speaker 1: percent accuracy, because our ability to read genes and identify
Speaker 1: mutations and sequences is never are going to be perfect.
Speaker 1: So what if a doctor told you you have a
Speaker 1: fifty percent chance of going bald or an eighty percent chance.
Speaker 1: Would that make you start treatments which have serious risks
Speaker 1: of side effects, or would you wait and see, knowing
Speaker 1: that starting treatments then might be too late, Or, as
Speaker 1: doctor Kyser argues, maybe it's better not to know, or
Speaker 1: maybe we should just accept that there's nothing wrong with
Speaker 1: being bald.
Speaker 3: No indeed, And actually I can tell you that this country,
Speaker 3: in the Netherlands, I'm not Dutch and Germans. I came
Speaker 3: here for work, so it's quite fashionable here to shave
Speaker 3: completely boiled. So I've never seen so many completely shaved persons.
Speaker 3: It's just fashionable.
Speaker 1: Wow. Maybe the real solution Niston moves to the Netherlands. Indeed,
Speaker 1: all right, there you have it. Maybe the real cure
Speaker 1: for baldness is for everyone to go Dutch to see
Speaker 1: it as normal or even beautiful. Thanks for joining us.
Speaker 1: See you next time you've been listening to Science Stuff.
Speaker 1: The production of iHeartRadio written and produced by me Or
Speaker 1: hitch Ham, credited by Rose Seguda, executive producer Jerry Rowland,
Speaker 1: and audio engineer and mixer Kasey peckram Hey. Thanks to
Speaker 1: our experts today. If you're interested, Doctor glenchen Kowski has
Speaker 1: written a book called Branding Baldness, published by Cambridge University
Speaker 1: Press that he has pushed to make open access, which
Speaker 1: means it's free for anyone to download. I also want
Speaker 1: to thank Professor Luis Garza of John Hopkins University for
Speaker 1: filling me in on a lot of the details of
Speaker 1: what we know about baldness. And you can follow me
Speaker 1: on social media. Just search for PhD Comics and the
Speaker 1: name of your favorite platform. Be sure to subscribe to
Speaker 1: Sign Stuff on the iHeartRadio app, Apple Podcasts or wherever
Speaker 1: you get your podcasts, and please tell your friends we'll
Speaker 1: be back next Wednesday with another episode