December 1, 2018 • 30 mins
Epigenetics is a fascinating field of genetics that studies how the epigenome and environmental, nutritional and social factors affect gene expression. Josh and Chuck explain how epigenetics works in this episode.
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Speaker 1 (00:00):
Hi, everyone, Can your grandfather's diet short in your life?
What does that even mean? Well, it turns out it's possible.
And I remember when we stumbled upon this topic in
June of two thousand ten, really really fascinating stuff for me.
And it turns out it's true. There is actually Well
how about this. I'm not going to ruin it, just
give it a listen to everyone, Can your grandfather's diet
(00:22):
shorten your life? Welcome to Stuff You Should Know from
house Stuff Works dot com. Hey, and welcome to the podcast.
I'm Josh Clark. There's Charles W. Chuck Bryant, and I'm
Charles W. Chuck Bryant, and I'm Josh Clark. And that
makes this stuff you should Know? Right. Yeah, So this
(00:46):
is our podcast. We've been doing it for a while,
and um, are you welcoming new listeners? Yeah, here's another one. Okay,
all right, and actually I'm pretty excited about this one.
I've been wanting to do this one for a while.
You've been bugging me. Epigenetics do it. Let's do it.
The cutting edge of research of human of of our
(01:06):
understanding of life, not just human, of all life. My
mind was blown. It's a pretty big deal, real big deal. So, Chuck,
you've heard of the genetic revolution. Charles Darwin, he had
a long beard. He loved sea turtles, that kind of thing.
He used a vacation in the Galapagos, right. He um
wrote on the origin of the species, and it was
(01:26):
a pretty groundbreaking book, I would say. So it's basically
what he came up with was we are driven by
our genes. Right, we have genetic code and our DNA,
and that makes us red headed, it makes us timid,
it makes us courageous, prone to cancer, right exactly, and
it makes us thick tongued alright sometimes yeah, and we
(01:50):
are slaves to these genes, right, there's nothing we can
do to alter and we get him from our parents.
But you know, if if we find out that over time,
being thick tongued is um say, advantageous to human survival,
we're all going to talk like me. But millions of
years from now, at least hundreds of thousands, it definitely does.
(02:12):
And I just look for it in the future, Okay,
when we're all running around with robot bodies. Um, there
was another guy, and actually Darwin, just to show off,
once came across a type of orchid, right, the moon orchid,
I believe it's what it's called. And it had a
very very deep um I guess pistol pistol or statement.
(02:35):
I can never keep those things apart. And the nectar
was down in there. And he looked at that flower
and said, you know what, there is an organism out there,
probably a flying organism that it has a probosist that
fits perfectly into that flower. It was a um hawk moth.
And sure enough a few a few years later, at
(02:55):
some point in time later, they discovered the hawk moth
and it was pretty much literal really made to fit. Right.
So there's another guy named Jean Baptiste Lamark, who I
know you've heard of as well, right, all and all
his lamarky and stuff. Right, he was he was about
sixty to eighty. He was working about sixty or so
years before Darwin. He had his own ideas based on giraffes. Right. Yes,
(03:16):
he said that giraffe's next grew to reach the food,
but it was just over the course of a few generations, right, right,
And that's kind of flies in the face of Darwin. Yeah, sure,
who said it takes hundreds of thousands of years with
this stuff called epigenetics that we're about to talk about today.
Suddenly people are starting to go back and look at Lamark,
who was kind of dismissed as a quack. Yeah, um,
(03:40):
and say, you know what, Lamark may have been right
in this one. Yeah, prepare for your minds to be melted.
Let's all I have to say. Let's talk about epigenetics,
Chuck and go. Josh's first talk about the genome. I
heard a computer reference analogy that I thought was was
pretty spot on. If you think of the genome as
(04:03):
computer hardware, then the epigenome would be the software that
tells the computer what to do and when to do it.
But in this case, the epigenome tells your cells what
to do, what kind of cells to be, when to
activate or deactivate. So, like I guess every cell or yeah,
the d n A in every cell in the human
(04:23):
body has the exact same DNA. Yes, you have like
half of your mother's and half of your father's and
it comes together and gives you your d n A. Right. Um.
And if you look at the DNA and every cell
from a uh, the kind of cell that makes up
your fingernail, what would that be a carat in a
site okay, to a sperm cell, right, very very specialized
(04:46):
type of cell. They all have the same d n A.
They have the same genes in there um. But what
makes them different and what makes a carat and a
site and a sperm cell those things are the the
tag on those genes. So some are turned off, some
are turned on, and in a specific combination, you have
either a kratinosite or sperm cell, or a neuron or
(05:11):
a cell that makes up your eyeball, all of that stuff. Yeah,
So it's essentially it's a chemical tag that literally changes
the physical structure of your genome. So it'll bind tightly,
let's say, to an inactive UH gene make it unreadable,
or it'll stretch out an active gene and make it
really accessible, physically changing it. And epigenetics means above the
(05:34):
genome because these tags, these they're called methyl tags, which
is what one hydrogen and two carbon carbon and hydrogen bundles. Yeah, okay,
so it's a group. It's a really simple um compound um.
But they they they attached to the gene and a
place where other proteins or enzymes normally would attach to
(05:56):
activate it. So basically what they do is block a
gene from being active beaded, and they can silence them. Yeah.
So it's like a light switch. Literally you can turn
off sun jeans and turn off others. Um. And the uh,
the honey bee actually is is a pretty good demonstration
of this. Did you read about honey bees? Okay, so
you've got a worker bee, right, which is a sterile,
(06:17):
kind of mindless dumb bee that just does what it's
supposed to do, no offense agreed. Hey, I'm all down
with may Day all right? Uh? And uh with um
a queen bee, you have this, Uh, First of all,
she can reproduce, she goes and kills other rival queens,
she does um kind of all sorts of other stuff
(06:39):
that a worker bee isn't capable of doing. Um. And
what they found was a queen bee. Queen bee larva
are raised in this royal jelly, right, which worker bees
secrete from their their heads. It's a nutrient rich jelly,
so the larva grows in it. And what they found, Yeah,
it sounds kind of good, doesn't it, just because of
the jelly part. What they found was that um, the
(07:02):
royal jelly has it adds a methyl tag to the
queen bee Larva's d n m T three gene. And
this gene is like literally the on off switch. If
this gene is on, it goes to the default worker.
Be right right. If it's off, then all the genes
that that make a queen be a queen bee are
(07:25):
able to be turned on. Crazy, isn't it so? Epigenetics
happens in bees as well? And mice. Yes, the they've
done a lot of studies with mice. Obviously in the
a goody gene in these mice, and they would they
experiment with um with these mice affecting basically turning on
and off the epigenetic switch. So an unmethylated gene would
(07:51):
affect the mouse's size and weight and then and then
coat color. It makes them real fat and like yellow, yeah,
instead of skinning and brown. Have you seen one of
these things? Yeah, they're huge. They should all be named Wilburg.
The cool thing is though they showed the difference between
the skinny brown one and the fat yellow one. But
then they also did experiments where they did half and half,
(08:13):
like turned on half of them and turned off half
of them. And they literally showed him in a sequence.
I don't know if you saw this picture, but they
went from fat yellow to skinny brown, and in between
they got thinner and with spotted coats along the way,
crazy like yellow and brown spotted coat. Yeah. It's that specific. Yeah.
And the one of the ways that they have found
that they can manipulate these what is it a goody Yeah,
(08:36):
the goody gene and these mice that I guess our
bread specifically for this gene to be easily observed or something, Yeah,
manipulated to UM is through diet. Right, So they've actually
taken a goody jeen mice mothers who are pregnant fed
him a bunch of UM B vitamins in their diet. Yeah,
(08:57):
and soy right, yeah, soy is a really easy easy
grab for B vitamins, U belief, right, UM fed these
these pregnant, big fat yellow, ugly mice B vitamins and
their kids came out that that healthy, skinny brown right. Um.
They had identical moms with the same like a goody gan,
(09:18):
same upbringing, same everything, just fed them in the normal
mouse diet without vitamin B and they had the big
fat yellow kids. So diet is a really big factor
in epigenetic changes. What Chuck and I are talking about
(09:47):
right now is that science has found evidence that you
can change the genetics of your children by eating be
vitamins or by being abused when you're pregnant. Well, see,
that's what gets me. Some of the diet like makes
(10:08):
a little bit of sense, But the fact that an
environmental stimulus placed on your mom or even your grandparents
can affect your children or grandchildren something you didn't even
experience at all, it's kind of unfair. And actually, I
have to tell you, the more I study this, the
more worried I am for my own child or children. Like. Really,
what they're finding is the decisions that you make, especially
(10:31):
at a youngish age, are going to affect several generations
because these what you're doing is adding metal tags. What
we're talking about is pretty much the definitive answer to
the nature and nurture debate. And what we're finding is
both you have nature, which is your genes and they're
very much active, but you have nurture, which is the environment.
(10:52):
Whether it's diet, whether it's stress, um, whether it's lack
of exercise. Your body responds to these changes by saying, okay,
all right, Well, then we need to if you're gonna
lay around and be fat, then we have to we
have to deactivate this Chaine, we will punish your grandkids,
and your grandkids who are trying to be normal are
going to be fat little kids that live you know,
(11:13):
shortened lives. And this is where it came from, right, Chuck,
Wasn't there there was a study in Sweden that kind
of broke this ground. Yeah, didn't they find that? Um,
it was a very isolated group of people in Sweden
and at the time they were very isolated at least
where they couldn't get help from the outside world, very
very readily. And I think they studied the famine in
(11:36):
that right, Well, they the famine affected the generations afterwards. Well,
they had like feast or famine. It was like an
agricultural town. And they looked at these agricultural records that
this town kept for some reason, like really detailed records
for throughout the nineteenth century, and some years there was
nothing and people starved death. The next year there was everything.
(11:59):
And they found that the grand parents, the grand fathers,
um who feasted and starved within a year of one another. Um,
they're grandkids lived in average of thirty two years shorter
or less. Then it's the same the grandkids of the
(12:22):
same people who didn't have that kind of feast or
famine experience in the same town right around, with the
same socio economic conditions. So yeah, that's three generations right there, right. Yeah.
Did you hear about the Angelman syndrome and the Prodavadi syndrome? No,
totally they I saw that. Actually, it was a PBS documentary.
(12:45):
The it's called The Ghost in Your Jeans. Did you
watch that, dude? It's on YouTube. It's in five, I
think five or six sections of ten minutes apiece. It's
a full show. Mind blowing. Uh. They found that there's
there's these two day print syndromes and I won't get
too deep into what they are, but Angelman syndrome and
uh Proda Villi syndrome is what it's called. And they
(13:08):
found the sons Italian prodovity. Sorry I dropped the ball there. Uh. Basically,
what causes each of these is a missing piece of
DNA and it can cause two different disease. Where they
found it and cause to these two different diseases, they're
completely unrelated depending on which parent it came from which
missing uh, part of the gene it came from. So basically, uh,
(13:32):
it's as if the gene knew where it was coming from.
Like gene imprinting, the gene had a memory that, Oh,
it came from the father, so you're gonna have Angelman syndrome,
or it came from the mother, so you're gonna have
prida evilly. Right, And this is a relatively recent discovery.
We were talking about them looking at agricultural records of
the u nineteenth century in Sweden. That was a doctor
named h Dr Lars olov Bygren, but he was working
(13:56):
in the mid eighties and he didn't really start to
lay the foundation of epigenetic research until the mid to
late nineties. So this is a very new field. But
what they're finding, and what Chuck was just saying, is
that your parents can pass on these epigenetic changes that
(14:17):
happen within themselves, right, Um, and your grandparents can too.
But this isn't supposed to happen. What happens when an
egg and a sperm meat, right, and it's like, hey,
here's half, here's my DNA, here's my DNA, and then
they get together. Um, there is actually a process where
these specialized cells go through and basically clean the d
(14:37):
n A of methyl tags. But they found that not
all methyl tags get cleaned off, so diet can affect
certain genes. These methyl tags can be passed down UM
and and with abuse as well. H Have you heard
about PTSD? Yeah, we passed down. They covered that in
the in that special as well. They did tests with
(15:01):
pregnant women who were in New York at the time
of nine eleven. Did you hear about this one? Yeah,
that's really recent study, right, Yeah, And they basically found
that pregnant women the experience that were pregnant at the
time the Towers came down and experienced post traumatic stress disorder.
They found that their babies had lower levels of cortisol
(15:22):
just like their moms did, which helps you deal with stress,
helps you how you deal with stress. So these little
babies inherited, basically inherited post traumatic stress disorder from their
mothers in the womb in utero and um. Cortisol it's
a hormone and it would be produced by a gene
or expressed by a gene, and how much or how
little is express depends on whether that gene is silenced
(15:45):
whether it's altered, and that alteration comes from methyal tags
which can be passed down, So PTSD can be passed down, right, Yeah,
and they're what they're speculating now that and this is
obviously speculation because these kids are still young, but they're
speculating that it's gonna happen to their kids as well,
and that's gonna be the real like gold nugget right
(16:07):
there there. They do go away eventually, they think mental tags, well,
they have in like fruit flies. With fruit flies, it's
like four generations, but fruit flies have a generation every
like five minutes and now um, and then I think
with mice it's like forty generations or something like that. Um.
And with humans, they expect it to be somewhere around
(16:27):
three maybe a few more. And then yeah, because what's
happening is our bodies are responding to environmental cues to change.
And then after those environmental cues go away, the body's like, okay,
well we can go back to normal now and get
rid of this methyl tag. So we've got nutrition. Right.
You are what you're You are what you eat, You
(16:49):
are what your parents eight, you are what your grandparents eight?
Uh and then there's um things like stress. Yeah, which
parenting right, And Yeah, I think they found with mice
mice mother's it didn't nurture their kids, um or nurse
their kids, uh, raise kids, produced kids that were kind
(17:09):
of jumpy and um, I guess had the mice version
of PTSD. And they theorized that the the body had
undergone an epigenetic change to prepare these mice for stressful
life where they need to be on guard. You know which,
if you think about it, chuck a blog post about this,
it's possible. What we call PTSD is an epigenetic change
(17:30):
that says you live in an environment where you can't
just you can't relax, so we're gonna make you jumpy,
you're gonna be edgy, and you're going to have flashbacks
so that you're always you know, on point. And it's
the result of an epigenetic change from a stressful event. Yeah,
and the same Yeah, I think you mentioned abuse earlier.
(17:50):
They found that one out of every five suicide victims
was a victim of child abuse as well. So they're
still kind of theorizing now, but they think there's a
positive correlation are between like you said, stressful upbringing in
an epigenetic change. So what else? Uh, well do you
I mean? And we're gonna talk about the good What
could be good about this? Potentially, yes, because it could
(18:11):
be really good. We're talking about and it's still early going.
We're talking about potentially curing things like Alzheimer's cancer, um,
mental disorders, uh, multiple sclerosis, you name its, thick tonguedness,
potentially being able to cure this because you can't. They
(18:32):
found that it's really hard to fix like a cancer cell.
And so what the doctors are thinking now is it's
really hard to fix a cancer cell, but it's a
whole lot easier to turn these epigenetic switches on and off,
which may in turn help defeat cancer. Like you want
to get a tumor suppressing gene going yeah, and then
(18:55):
but you want to get a cellular growth gene turned
down a little bit right like that, and that you
just cured cancer. Yeah. This This one doctor put it
like this. He said that, Um, it's almost like a
diplomacy instead of a war, Like you'll go tell the cell, hey,
you're a good human cell. You don't need to behave
this way. You should not be behaving this way. Yes,
(19:15):
it's called as a citadine. It's good to me as
a citadine. It was originally marketed for UM something else entirely,
probably Alzheimer's. Everything was uh, and then they come up
with they figure out that it's actually UM turning down
these growth cells are these growth genes, and they say, hey,
(19:37):
how about we use this for leukemia? Right boom being
there you go. Yeah, people all of a sudden in
remission where they hadn't been before. So it's pretty pretty startling. Yeah,
it's still in the early stages though, right. Uh. The
other thing too is you can you can. It's it's
easier to fix the epigenome. That's the good news. As
(19:58):
we move forward, it's also a lot easier to mess
up your own epigenome diet and smoking and things like that. Yeah,
there was a the guy who was studying Sweden hooked
up with a guy who proposed, uh, the entire field
of epigenetics in and then they got together with another
(20:19):
researcher who was running that. You remember the framing Framinghamton Farmington.
Is it farming him, farming him, framing him, framing him
that the Massachusetts study, the Heart study Umber forty years
long or something, right, remember Great Britain's version of It's
like the Avon Longitudinal study. Okay, so this guy had
(20:40):
a friend who had access to these these files, and
what they found was that one and sixty six fathers
in this study had started smoking around age eleven. Uh.
And so they started looking at these these guys and
found that their kids were shorter and fatter and just
generally unhealthy or than other kids, even controlling for other
(21:02):
factors as well. So smoking is a problem. Drugs are
a problem. Cocaine addicted mice past memory problems onto three
generations of their offspring. Yeah, it said that cocaine, especially
tripp triggers epigenetic changes that affect like hundreds of genes
at the same time, which because memories just such a
complex process. So don't do cocaine, no, and don't smoke.
(21:28):
It's just a bad idea, especially at a young age.
And Chuck, there's a project underway, you remember, the Human
Genome project, completed in March of two thousand, which is
now that they're kind of like exactly. There was a
did you read this time article at the end of
it that the author is talking about the epigenome project.
(21:49):
That's the big daddy, right, And he was saying that
the Human Epigenome Project is going to make the Human
Genome Project look like the homework that sixteenth century school
kids did on their advocate this. Think about this. What
they found in the Human Genome Project is twenty seven
thousand genes that are mapped. Right, Um, just just fiddling
(22:13):
with these combinations increases the map that needs to be
created exponentially, right, Like Domino's Pizza has twenty seven ingredients
they produces they do. I went counting, the produces eighty
eight million different combinations from twenty seven I imagine twenty
seven thousand ingredients. How many different combinations is that produced?
(22:33):
This is the scope of the Human Epigenome Project that's underway. Now,
what what about Pizza Hut with all their like stuff
crust and eat it backwards and the ingredients are underneath
your pizza and probably even more stuffed. Yeah, but I
think Dominos has more pizza because they've got like the
Philly cheese steak one, and they have like the cheeseburger,
(22:54):
the bacon cheeseburger, which yeah, they did, like the Ruben
sandwich pizza that would be very good, would be good.
So epigenetics is changing everything I think, and it's core.
It's going to it's going to point out that all
of our understanding of medicine is just an odd way
of describing an epigenetic change, you know, like psychology, psychiatry.
(23:19):
I predict that our future and complete understanding of humanity
is going to be a combination of sociology and epigenetics.
So we we thought we were onto something with me
or neurons, but forget what we said. Not just kidding,
Actually I think that you could probably explain that epigenetically
and with sociology as well. Have you heard of this guy,
(23:40):
Dr Bruce Lipton. He is, he's got a documentary out
called The Living Matrix, And at first I was reading
and I was like, Wow, this guy's really onto something.
But then I started reading other people saying this guy's
a quack. Oh yeah, yeah. He basically he's a big
epigenetics guy. But he thinks that your brain can essentially
change your genetic expression by manipulating the epigenome, like concentrating.
(24:05):
He thinks the placebo effect could potentially be explained by this,
and like spontaneous remission and cancer, spontaneous combustion. Spontaneous remission
obviously is when you go into remission with no known cause,
not from you know, any treatment. And he says this
is explained because you're you have a profound change in
your perception of your life and what life is all about,
(24:28):
and that can potentially alter the epigenome. Well, you could
also make a case that this guy, what this guy
is talking about is decreasing stress, which stresses freaks havoc
on us and could create methtyal tags and alter gene expression.
So maybe he's just using a quacky way of describing
lowering your own stress levels by increasing self confidence. It's
(24:52):
interesting when you see these people, though, and you watch
a YouTube video and you think, oh my gosh, that's
the secret to the future, and then you see all
these other people go that guy is such a quack. Yeah,
but at the same time you could you could say, well,
maybe those other people are unmagenitive. Good point. So if
(25:27):
you want to learn more about epigenetics, I strongly recommend
University of Utah's website it Um, have you been on
a chuck Why didn't you recommend that to me? Did
you see it? I don't think so. I did. There's
like a month ago when uh, yeah, you can turn
up gene expression turn it down. It's like, um, a
(25:47):
lot of foods that you should eat if you want
to alter yourself epigenetically, especially if you're pregnant. Or go
to YouTube and watch the Ghost in your Genes PBS.
It is literally mind blowing, well not literally, people always
say literally. It's figured talk about changing your genetic expression.
And if you want to read some very beautiful prose
(26:10):
on epigenetics, uh shock full of flight simulator references, read
uh how epigenetics works by typing epigenetics in the handy
search bar at how stuffworks dot com, Which means it's
time for listener mail. Yes, indeed, Josh, Josh, you remember
Sarah the amazing eleven year old fan it's not eleven anymore,
(26:33):
who captured our hearts when she first emailed early on
in the days of podcastings to do like she was
one of the first fans. Actually, yeah, Sarah the amazing
eleven year old fan is now Sarah the amazing thirteen
year old fan. Gosh, I feel so old. Now. We
shouldn't do this a while? Well, yeah, and we should
keep like once a year, we should update people on
Sarah's age. And then when she graduate, if we're still
(26:55):
doing this in five years, when she graduates college, we
should go like a high school. Yeah, you should go
to her graduation ors, we should give the commencement speech.
She should I call valedictorian. Well yeah, and then the
prince would be like, who are you guys? Can we
get security in here? We'll say I'm the valedictorian. He's
a salutatorian. What do you mean? Uh? So this comes
from Sarah. She checked someone that's from time to time,
(27:16):
and she's still just as cute at thirteen. She's not
all bratty now that she's a teenager. Hello to some
of my favorite people. Today, I earned some strange looks
from people about my knowledge of legos or Lego bricks.
I also tried making a sphere of Lego, but I
couldn't figure it out. Also, today's my birthday. I'm really
excited that I'm finally a teen Yahoo. Do you remember
(27:38):
what I asked for and what she asked for? She's
got a blog now, and she asked if one of
us could comment on her blog. And I went to
her blog and commented. And her blog is basically her
and her little friend talking back and forth to each
other about stuff. It got their eyes with hearts. No, well,
I don't think you can do that, but it is really,
really cute, and I'm actually gonna encourage people to go
(28:02):
to her blog. I hope she gets mad traffic and
her blog Josh is Sarah loves Australian commercials dot webs
dot com. And here's the clincher. It is s A
s A r w h. There's no www right now
and she missed spells Australian all over the place. Um
she spells it A U S t r A I
(28:26):
l I A n. So it's like OUs trail I
N hey I A n right, so spell the whole
U r l h t t P colon slash slash
s A r A h l O v E s
A U S t r A I l I A
(28:47):
n c O M M E r c I A
l s dot webs w e b s dot com.
And I hope people come right there and check it out.
I hope so too. Um. So she turned thirteen, she says,
by the way, can you please not tell Kristin, Molly
or Katie that I think you guys are better than them.
I think that would be kind of like bragging. It
(29:10):
would be kind of like bragging, which is why we
would never do. We would never tell them, and they
I'm sure they don't listen to our shows, so they'll
never know. And then she closes and this is Emily
just thought, this is the cutest thing ever. Well, so long, farewell,
our al vetter saying goodbye, a do a do to
you and you and you, and then in print the
scene she says, in case you didn't know, that was
(29:30):
from the sound of music. Ye, so long farewell. Yeah,
and that's one of Emily's favorite Well, you should sing
the rest of it. Do a doe doe do? You?
And you and you so Sarah, happy birthday. You're awesome.
You're a dedicated fan. We just think you're super cool.
And good luck with the blog if you do learn
(29:51):
how to doe eyes with heart. We want to know, Sarah,
Happy birthday to you. If you want to become a
fan who's captured our arts, send us something interesting. We
want to uh, we want another super fan and be
a cute little kid. Otherwise you're not gonna culture that
helps as well. Broken English doesn't hurt too true. Uh.
You can send an email to stuff Podcast at how
(30:15):
stuff works dot com. For more on this and thousands
of other topics, visit how stuff works dot com. Want
more how stuff works, check out our blogs on the
house stuff works dot com home page
Hi, everyone, Can your grandfather's diet short in your life?
What does that even mean? Well, it turns out it's possible.
And I remember when we stumbled upon this topic in
June of two thousand ten, really really fascinating stuff for me.
And it turns out it's true. There is actually Well
how about this. I'm not going to ruin it, just
give it a listen to everyone, Can your grandfather's diet
(00:22):
shorten your life? Welcome to Stuff You Should Know from
house Stuff Works dot com. Hey, and welcome to the podcast.
I'm Josh Clark. There's Charles W. Chuck Bryant, and I'm
Charles W. Chuck Bryant, and I'm Josh Clark. And that
makes this stuff you should Know? Right. Yeah, So this
(00:46):
is our podcast. We've been doing it for a while,
and um, are you welcoming new listeners? Yeah, here's another one. Okay,
all right, and actually I'm pretty excited about this one.
I've been wanting to do this one for a while.
You've been bugging me. Epigenetics do it. Let's do it.
The cutting edge of research of human of of our
(01:06):
understanding of life, not just human, of all life. My
mind was blown. It's a pretty big deal, real big deal. So, Chuck,
you've heard of the genetic revolution. Charles Darwin, he had
a long beard. He loved sea turtles, that kind of thing.
He used a vacation in the Galapagos, right. He um
wrote on the origin of the species, and it was
(01:26):
a pretty groundbreaking book, I would say. So it's basically
what he came up with was we are driven by
our genes. Right, we have genetic code and our DNA,
and that makes us red headed, it makes us timid,
it makes us courageous, prone to cancer, right exactly, and
it makes us thick tongued alright sometimes yeah, and we
(01:50):
are slaves to these genes, right, there's nothing we can
do to alter and we get him from our parents.
But you know, if if we find out that over time,
being thick tongued is um say, advantageous to human survival,
we're all going to talk like me. But millions of
years from now, at least hundreds of thousands, it definitely does.
(02:12):
And I just look for it in the future, Okay,
when we're all running around with robot bodies. Um, there
was another guy, and actually Darwin, just to show off,
once came across a type of orchid, right, the moon orchid,
I believe it's what it's called. And it had a
very very deep um I guess pistol pistol or statement.
(02:35):
I can never keep those things apart. And the nectar
was down in there. And he looked at that flower
and said, you know what, there is an organism out there,
probably a flying organism that it has a probosist that
fits perfectly into that flower. It was a um hawk moth.
And sure enough a few a few years later, at
(02:55):
some point in time later, they discovered the hawk moth
and it was pretty much literal really made to fit. Right.
So there's another guy named Jean Baptiste Lamark, who I
know you've heard of as well, right, all and all
his lamarky and stuff. Right, he was he was about
sixty to eighty. He was working about sixty or so
years before Darwin. He had his own ideas based on giraffes. Right. Yes,
(03:16):
he said that giraffe's next grew to reach the food,
but it was just over the course of a few generations, right, right,
And that's kind of flies in the face of Darwin. Yeah, sure,
who said it takes hundreds of thousands of years with
this stuff called epigenetics that we're about to talk about today.
Suddenly people are starting to go back and look at Lamark,
who was kind of dismissed as a quack. Yeah, um,
(03:40):
and say, you know what, Lamark may have been right
in this one. Yeah, prepare for your minds to be melted.
Let's all I have to say. Let's talk about epigenetics,
Chuck and go. Josh's first talk about the genome. I
heard a computer reference analogy that I thought was was
pretty spot on. If you think of the genome as
(04:03):
computer hardware, then the epigenome would be the software that
tells the computer what to do and when to do it.
But in this case, the epigenome tells your cells what
to do, what kind of cells to be, when to
activate or deactivate. So, like I guess every cell or yeah,
the d n A in every cell in the human
(04:23):
body has the exact same DNA. Yes, you have like
half of your mother's and half of your father's and
it comes together and gives you your d n A. Right. Um.
And if you look at the DNA and every cell
from a uh, the kind of cell that makes up
your fingernail, what would that be a carat in a
site okay, to a sperm cell, right, very very specialized
(04:46):
type of cell. They all have the same d n A.
They have the same genes in there um. But what
makes them different and what makes a carat and a
site and a sperm cell those things are the the
tag on those genes. So some are turned off, some
are turned on, and in a specific combination, you have
either a kratinosite or sperm cell, or a neuron or
(05:11):
a cell that makes up your eyeball, all of that stuff. Yeah,
So it's essentially it's a chemical tag that literally changes
the physical structure of your genome. So it'll bind tightly,
let's say, to an inactive UH gene make it unreadable,
or it'll stretch out an active gene and make it
really accessible, physically changing it. And epigenetics means above the
(05:34):
genome because these tags, these they're called methyl tags, which
is what one hydrogen and two carbon carbon and hydrogen bundles. Yeah, okay,
so it's a group. It's a really simple um compound um.
But they they they attached to the gene and a
place where other proteins or enzymes normally would attach to
(05:56):
activate it. So basically what they do is block a
gene from being active beaded, and they can silence them. Yeah.
So it's like a light switch. Literally you can turn
off sun jeans and turn off others. Um. And the uh,
the honey bee actually is is a pretty good demonstration
of this. Did you read about honey bees? Okay, so
you've got a worker bee, right, which is a sterile,
(06:17):
kind of mindless dumb bee that just does what it's
supposed to do, no offense agreed. Hey, I'm all down
with may Day all right? Uh? And uh with um
a queen bee, you have this, Uh, First of all,
she can reproduce, she goes and kills other rival queens,
she does um kind of all sorts of other stuff
(06:39):
that a worker bee isn't capable of doing. Um. And
what they found was a queen bee. Queen bee larva
are raised in this royal jelly, right, which worker bees
secrete from their their heads. It's a nutrient rich jelly,
so the larva grows in it. And what they found, Yeah,
it sounds kind of good, doesn't it, just because of
the jelly part. What they found was that um, the
(07:02):
royal jelly has it adds a methyl tag to the
queen bee Larva's d n m T three gene. And
this gene is like literally the on off switch. If
this gene is on, it goes to the default worker.
Be right right. If it's off, then all the genes
that that make a queen be a queen bee are
(07:25):
able to be turned on. Crazy, isn't it so? Epigenetics
happens in bees as well? And mice. Yes, the they've
done a lot of studies with mice. Obviously in the
a goody gene in these mice, and they would they
experiment with um with these mice affecting basically turning on
and off the epigenetic switch. So an unmethylated gene would
(07:51):
affect the mouse's size and weight and then and then
coat color. It makes them real fat and like yellow, yeah,
instead of skinning and brown. Have you seen one of
these things? Yeah, they're huge. They should all be named Wilburg.
The cool thing is though they showed the difference between
the skinny brown one and the fat yellow one. But
then they also did experiments where they did half and half,
(08:13):
like turned on half of them and turned off half
of them. And they literally showed him in a sequence.
I don't know if you saw this picture, but they
went from fat yellow to skinny brown, and in between
they got thinner and with spotted coats along the way,
crazy like yellow and brown spotted coat. Yeah. It's that specific. Yeah.
And the one of the ways that they have found
that they can manipulate these what is it a goody Yeah,
(08:36):
the goody gene and these mice that I guess our
bread specifically for this gene to be easily observed or something, Yeah,
manipulated to UM is through diet. Right, So they've actually
taken a goody jeen mice mothers who are pregnant fed
him a bunch of UM B vitamins in their diet. Yeah,
(08:57):
and soy right, yeah, soy is a really easy easy
grab for B vitamins, U belief, right, UM fed these
these pregnant, big fat yellow, ugly mice B vitamins and
their kids came out that that healthy, skinny brown right. Um.
They had identical moms with the same like a goody gan,
(09:18):
same upbringing, same everything, just fed them in the normal
mouse diet without vitamin B and they had the big
fat yellow kids. So diet is a really big factor
in epigenetic changes. What Chuck and I are talking about
(09:47):
right now is that science has found evidence that you
can change the genetics of your children by eating be
vitamins or by being abused when you're pregnant. Well, see,
that's what gets me. Some of the diet like makes
(10:08):
a little bit of sense, But the fact that an
environmental stimulus placed on your mom or even your grandparents
can affect your children or grandchildren something you didn't even
experience at all, it's kind of unfair. And actually, I
have to tell you, the more I study this, the
more worried I am for my own child or children. Like. Really,
what they're finding is the decisions that you make, especially
(10:31):
at a youngish age, are going to affect several generations
because these what you're doing is adding metal tags. What
we're talking about is pretty much the definitive answer to
the nature and nurture debate. And what we're finding is
both you have nature, which is your genes and they're
very much active, but you have nurture, which is the environment.
(10:52):
Whether it's diet, whether it's stress, um, whether it's lack
of exercise. Your body responds to these changes by saying, okay,
all right, Well, then we need to if you're gonna
lay around and be fat, then we have to we
have to deactivate this Chaine, we will punish your grandkids,
and your grandkids who are trying to be normal are
going to be fat little kids that live you know,
(11:13):
shortened lives. And this is where it came from, right, Chuck,
Wasn't there there was a study in Sweden that kind
of broke this ground. Yeah, didn't they find that? Um,
it was a very isolated group of people in Sweden
and at the time they were very isolated at least
where they couldn't get help from the outside world, very
very readily. And I think they studied the famine in
(11:36):
that right, Well, they the famine affected the generations afterwards. Well,
they had like feast or famine. It was like an
agricultural town. And they looked at these agricultural records that
this town kept for some reason, like really detailed records
for throughout the nineteenth century, and some years there was
nothing and people starved death. The next year there was everything.
(11:59):
And they found that the grand parents, the grand fathers,
um who feasted and starved within a year of one another. Um,
they're grandkids lived in average of thirty two years shorter
or less. Then it's the same the grandkids of the
(12:22):
same people who didn't have that kind of feast or
famine experience in the same town right around, with the
same socio economic conditions. So yeah, that's three generations right there, right. Yeah.
Did you hear about the Angelman syndrome and the Prodavadi syndrome? No,
totally they I saw that. Actually, it was a PBS documentary.
(12:45):
The it's called The Ghost in Your Jeans. Did you
watch that, dude? It's on YouTube. It's in five, I
think five or six sections of ten minutes apiece. It's
a full show. Mind blowing. Uh. They found that there's
there's these two day print syndromes and I won't get
too deep into what they are, but Angelman syndrome and
uh Proda Villi syndrome is what it's called. And they
(13:08):
found the sons Italian prodovity. Sorry I dropped the ball there. Uh. Basically,
what causes each of these is a missing piece of
DNA and it can cause two different disease. Where they
found it and cause to these two different diseases, they're
completely unrelated depending on which parent it came from which
missing uh, part of the gene it came from. So basically, uh,
(13:32):
it's as if the gene knew where it was coming from.
Like gene imprinting, the gene had a memory that, Oh,
it came from the father, so you're gonna have Angelman syndrome,
or it came from the mother, so you're gonna have
prida evilly. Right, And this is a relatively recent discovery.
We were talking about them looking at agricultural records of
the u nineteenth century in Sweden. That was a doctor
named h Dr Lars olov Bygren, but he was working
(13:56):
in the mid eighties and he didn't really start to
lay the foundation of epigenetic research until the mid to
late nineties. So this is a very new field. But
what they're finding, and what Chuck was just saying, is
that your parents can pass on these epigenetic changes that
(14:17):
happen within themselves, right, Um, and your grandparents can too.
But this isn't supposed to happen. What happens when an
egg and a sperm meat, right, and it's like, hey,
here's half, here's my DNA, here's my DNA, and then
they get together. Um, there is actually a process where
these specialized cells go through and basically clean the d
(14:37):
n A of methyl tags. But they found that not
all methyl tags get cleaned off, so diet can affect
certain genes. These methyl tags can be passed down UM
and and with abuse as well. H Have you heard
about PTSD? Yeah, we passed down. They covered that in
the in that special as well. They did tests with
(15:01):
pregnant women who were in New York at the time
of nine eleven. Did you hear about this one? Yeah,
that's really recent study, right, Yeah, And they basically found
that pregnant women the experience that were pregnant at the
time the Towers came down and experienced post traumatic stress disorder.
They found that their babies had lower levels of cortisol
(15:22):
just like their moms did, which helps you deal with stress,
helps you how you deal with stress. So these little
babies inherited, basically inherited post traumatic stress disorder from their
mothers in the womb in utero and um. Cortisol it's
a hormone and it would be produced by a gene
or expressed by a gene, and how much or how
little is express depends on whether that gene is silenced
(15:45):
whether it's altered, and that alteration comes from methyal tags
which can be passed down, So PTSD can be passed down, right, Yeah,
and they're what they're speculating now that and this is
obviously speculation because these kids are still young, but they're
speculating that it's gonna happen to their kids as well,
and that's gonna be the real like gold nugget right
(16:07):
there there. They do go away eventually, they think mental tags, well,
they have in like fruit flies. With fruit flies, it's
like four generations, but fruit flies have a generation every
like five minutes and now um, and then I think
with mice it's like forty generations or something like that. Um.
And with humans, they expect it to be somewhere around
(16:27):
three maybe a few more. And then yeah, because what's
happening is our bodies are responding to environmental cues to change.
And then after those environmental cues go away, the body's like, okay,
well we can go back to normal now and get
rid of this methyl tag. So we've got nutrition. Right.
You are what you're You are what you eat, You
(16:49):
are what your parents eight, you are what your grandparents eight?
Uh and then there's um things like stress. Yeah, which
parenting right, And Yeah, I think they found with mice
mice mother's it didn't nurture their kids, um or nurse
their kids, uh, raise kids, produced kids that were kind
(17:09):
of jumpy and um, I guess had the mice version
of PTSD. And they theorized that the the body had
undergone an epigenetic change to prepare these mice for stressful
life where they need to be on guard. You know which,
if you think about it, chuck a blog post about this,
it's possible. What we call PTSD is an epigenetic change
(17:30):
that says you live in an environment where you can't
just you can't relax, so we're gonna make you jumpy,
you're gonna be edgy, and you're going to have flashbacks
so that you're always you know, on point. And it's
the result of an epigenetic change from a stressful event. Yeah,
and the same Yeah, I think you mentioned abuse earlier.
(17:50):
They found that one out of every five suicide victims
was a victim of child abuse as well. So they're
still kind of theorizing now, but they think there's a
positive correlation are between like you said, stressful upbringing in
an epigenetic change. So what else? Uh, well do you
I mean? And we're gonna talk about the good What
could be good about this? Potentially, yes, because it could
(18:11):
be really good. We're talking about and it's still early going.
We're talking about potentially curing things like Alzheimer's cancer, um,
mental disorders, uh, multiple sclerosis, you name its, thick tonguedness,
potentially being able to cure this because you can't. They
(18:32):
found that it's really hard to fix like a cancer cell.
And so what the doctors are thinking now is it's
really hard to fix a cancer cell, but it's a
whole lot easier to turn these epigenetic switches on and off,
which may in turn help defeat cancer. Like you want
to get a tumor suppressing gene going yeah, and then
(18:55):
but you want to get a cellular growth gene turned
down a little bit right like that, and that you
just cured cancer. Yeah. This This one doctor put it
like this. He said that, Um, it's almost like a
diplomacy instead of a war, Like you'll go tell the cell, hey,
you're a good human cell. You don't need to behave
this way. You should not be behaving this way. Yes,
(19:15):
it's called as a citadine. It's good to me as
a citadine. It was originally marketed for UM something else entirely,
probably Alzheimer's. Everything was uh, and then they come up
with they figure out that it's actually UM turning down
these growth cells are these growth genes, and they say, hey,
(19:37):
how about we use this for leukemia? Right boom being
there you go. Yeah, people all of a sudden in
remission where they hadn't been before. So it's pretty pretty startling. Yeah,
it's still in the early stages though, right. Uh. The
other thing too is you can you can. It's it's
easier to fix the epigenome. That's the good news. As
(19:58):
we move forward, it's also a lot easier to mess
up your own epigenome diet and smoking and things like that. Yeah,
there was a the guy who was studying Sweden hooked
up with a guy who proposed, uh, the entire field
of epigenetics in and then they got together with another
(20:19):
researcher who was running that. You remember the framing Framinghamton Farmington.
Is it farming him, farming him, framing him, framing him
that the Massachusetts study, the Heart study Umber forty years
long or something, right, remember Great Britain's version of It's
like the Avon Longitudinal study. Okay, so this guy had
(20:40):
a friend who had access to these these files, and
what they found was that one and sixty six fathers
in this study had started smoking around age eleven. Uh.
And so they started looking at these these guys and
found that their kids were shorter and fatter and just
generally unhealthy or than other kids, even controlling for other
(21:02):
factors as well. So smoking is a problem. Drugs are
a problem. Cocaine addicted mice past memory problems onto three
generations of their offspring. Yeah, it said that cocaine, especially
tripp triggers epigenetic changes that affect like hundreds of genes
at the same time, which because memories just such a
complex process. So don't do cocaine, no, and don't smoke.
(21:28):
It's just a bad idea, especially at a young age.
And Chuck, there's a project underway, you remember, the Human
Genome project, completed in March of two thousand, which is
now that they're kind of like exactly. There was a
did you read this time article at the end of
it that the author is talking about the epigenome project.
(21:49):
That's the big daddy, right, And he was saying that
the Human Epigenome Project is going to make the Human
Genome Project look like the homework that sixteenth century school
kids did on their advocate this. Think about this. What
they found in the Human Genome Project is twenty seven
thousand genes that are mapped. Right, Um, just just fiddling
(22:13):
with these combinations increases the map that needs to be
created exponentially, right, Like Domino's Pizza has twenty seven ingredients
they produces they do. I went counting, the produces eighty
eight million different combinations from twenty seven I imagine twenty
seven thousand ingredients. How many different combinations is that produced?
(22:33):
This is the scope of the Human Epigenome Project that's underway. Now,
what what about Pizza Hut with all their like stuff
crust and eat it backwards and the ingredients are underneath
your pizza and probably even more stuffed. Yeah, but I
think Dominos has more pizza because they've got like the
Philly cheese steak one, and they have like the cheeseburger,
(22:54):
the bacon cheeseburger, which yeah, they did, like the Ruben
sandwich pizza that would be very good, would be good.
So epigenetics is changing everything I think, and it's core.
It's going to it's going to point out that all
of our understanding of medicine is just an odd way
of describing an epigenetic change, you know, like psychology, psychiatry.
(23:19):
I predict that our future and complete understanding of humanity
is going to be a combination of sociology and epigenetics.
So we we thought we were onto something with me
or neurons, but forget what we said. Not just kidding,
Actually I think that you could probably explain that epigenetically
and with sociology as well. Have you heard of this guy,
(23:40):
Dr Bruce Lipton. He is, he's got a documentary out
called The Living Matrix, And at first I was reading
and I was like, Wow, this guy's really onto something.
But then I started reading other people saying this guy's
a quack. Oh yeah, yeah. He basically he's a big
epigenetics guy. But he thinks that your brain can essentially
change your genetic expression by manipulating the epigenome, like concentrating.
(24:05):
He thinks the placebo effect could potentially be explained by this,
and like spontaneous remission and cancer, spontaneous combustion. Spontaneous remission
obviously is when you go into remission with no known cause,
not from you know, any treatment. And he says this
is explained because you're you have a profound change in
your perception of your life and what life is all about,
(24:28):
and that can potentially alter the epigenome. Well, you could
also make a case that this guy, what this guy
is talking about is decreasing stress, which stresses freaks havoc
on us and could create methtyal tags and alter gene expression.
So maybe he's just using a quacky way of describing
lowering your own stress levels by increasing self confidence. It's
(24:52):
interesting when you see these people, though, and you watch
a YouTube video and you think, oh my gosh, that's
the secret to the future, and then you see all
these other people go that guy is such a quack. Yeah,
but at the same time you could you could say, well,
maybe those other people are unmagenitive. Good point. So if
(25:27):
you want to learn more about epigenetics, I strongly recommend
University of Utah's website it Um, have you been on
a chuck Why didn't you recommend that to me? Did
you see it? I don't think so. I did. There's
like a month ago when uh, yeah, you can turn
up gene expression turn it down. It's like, um, a
(25:47):
lot of foods that you should eat if you want
to alter yourself epigenetically, especially if you're pregnant. Or go
to YouTube and watch the Ghost in your Genes PBS.
It is literally mind blowing, well not literally, people always
say literally. It's figured talk about changing your genetic expression.
And if you want to read some very beautiful prose
(26:10):
on epigenetics, uh shock full of flight simulator references, read
uh how epigenetics works by typing epigenetics in the handy
search bar at how stuffworks dot com, Which means it's
time for listener mail. Yes, indeed, Josh, Josh, you remember
Sarah the amazing eleven year old fan it's not eleven anymore,
(26:33):
who captured our hearts when she first emailed early on
in the days of podcastings to do like she was
one of the first fans. Actually, yeah, Sarah the amazing
eleven year old fan is now Sarah the amazing thirteen
year old fan. Gosh, I feel so old. Now. We
shouldn't do this a while? Well, yeah, and we should
keep like once a year, we should update people on
Sarah's age. And then when she graduate, if we're still
(26:55):
doing this in five years, when she graduates college, we
should go like a high school. Yeah, you should go
to her graduation ors, we should give the commencement speech.
She should I call valedictorian. Well yeah, and then the
prince would be like, who are you guys? Can we
get security in here? We'll say I'm the valedictorian. He's
a salutatorian. What do you mean? Uh? So this comes
from Sarah. She checked someone that's from time to time,
(27:16):
and she's still just as cute at thirteen. She's not
all bratty now that she's a teenager. Hello to some
of my favorite people. Today, I earned some strange looks
from people about my knowledge of legos or Lego bricks.
I also tried making a sphere of Lego, but I
couldn't figure it out. Also, today's my birthday. I'm really
excited that I'm finally a teen Yahoo. Do you remember
(27:38):
what I asked for and what she asked for? She's
got a blog now, and she asked if one of
us could comment on her blog. And I went to
her blog and commented. And her blog is basically her
and her little friend talking back and forth to each
other about stuff. It got their eyes with hearts. No, well,
I don't think you can do that, but it is really,
really cute, and I'm actually gonna encourage people to go
(28:02):
to her blog. I hope she gets mad traffic and
her blog Josh is Sarah loves Australian commercials dot webs
dot com. And here's the clincher. It is s A
s A r w h. There's no www right now
and she missed spells Australian all over the place. Um
she spells it A U S t r A I
(28:26):
l I A n. So it's like OUs trail I
N hey I A n right, so spell the whole
U r l h t t P colon slash slash
s A r A h l O v E s
A U S t r A I l I A
(28:47):
n c O M M E r c I A
l s dot webs w e b s dot com.
And I hope people come right there and check it out.
I hope so too. Um. So she turned thirteen, she says,
by the way, can you please not tell Kristin, Molly
or Katie that I think you guys are better than them.
I think that would be kind of like bragging. It
(29:10):
would be kind of like bragging, which is why we
would never do. We would never tell them, and they
I'm sure they don't listen to our shows, so they'll
never know. And then she closes and this is Emily
just thought, this is the cutest thing ever. Well, so long, farewell,
our al vetter saying goodbye, a do a do to
you and you and you, and then in print the
scene she says, in case you didn't know, that was
(29:30):
from the sound of music. Ye, so long farewell. Yeah,
and that's one of Emily's favorite Well, you should sing
the rest of it. Do a doe doe do? You?
And you and you so Sarah, happy birthday. You're awesome.
You're a dedicated fan. We just think you're super cool.
And good luck with the blog if you do learn
(29:51):
how to doe eyes with heart. We want to know, Sarah,
Happy birthday to you. If you want to become a
fan who's captured our arts, send us something interesting. We
want to uh, we want another super fan and be
a cute little kid. Otherwise you're not gonna culture that
helps as well. Broken English doesn't hurt too true. Uh.
You can send an email to stuff Podcast at how
(30:15):
stuff works dot com. For more on this and thousands
of other topics, visit how stuff works dot com. Want
more how stuff works, check out our blogs on the
house stuff works dot com home page
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