Cracked Science 24: Epigenetics: the Science
and the Chopra
This week on Cracked Science: epigenetics
is cool, and some people even think it will
turn you into Jesus.
[TITLE]
Hey, this is Jonathan Jarry and you're watching
Cracked Science, the show from the McGill
Office for Science and Society that separates
sense from nonsense on the scientific stage.
Our topic today is epigenetics.
Epigenetics is like Daniel Baldwin.
You know Alec really well, you're familiar
with Billy and Stephen, but Daniel is the
one you've vaguely heard of but have no idea
what he does.
For your information, he was in Stripperland,
a movie about a virus that turns women into
carnivorous zombie strippers.
Daniel is also featured on the soundtrack,
rapping.
The more you know....
Epigenetics is a word you'll hear more and
more in the media and, content warning, this
story ends with Deepak Chopra.
To define epigenetics, let's focus on baking.
You may remember my analogy from episode 14.
Genes make proteins, but genes aren't *always*
making proteins.
It's like a bread maker making bread: they
make baguettes and ciabattas during the day,
but they sleep at night.
Before a big holiday, they may get an increase
in customers and they have to work longer
and make more bread.
It's the same situation with a gene: how much
protein it makes depends on a number of factors.
These factors, collectively, are known as
the epigenome and the field that studies it
is called epigenetics.
And how the epigenome influences how much
"bread" is being made can be explained rather
simply.
You see, DNA needs to be physically accessible
so that proteins can be made from it, just
like a baker's hands need to be free for her
to make bread.
[VIDEO: HISTONE DEACETYLATION]
Keep an eye on the DNA helix and what happens
to it when a cascade of events is put into
motion by a simple epigenetic mark.
The DNA close to that mark turns into a ball.
It gets compressed and it can't be accessed
anymore.
That stretch of DNA is now silent.
Not yet, Deepak!
We're not done with the science!
When you hear me say "consciousness", you
can come out.
Perhaps the most interesting thing about our
epigenome is that it changes.
Our DNA sequence-the As and Ts and all that-that
doesn't change very much in our lifetime,
except for the odd mutation, but our epigenome
is plastic.
It responds to our environment.
As far as we know, pretty much anything *can*
change our epigenome.
The lifestyle of our mom when we're in the
womb, UV radiation, exposure to various environmental
chemicals like lead and arsenic, consumption
of alcohol, stress, and diet, especially whether
or not our mom's diet had enough folate in
it when they were pregnant.
These exposures can alter our epigenome even
when we're in the womb.
Now, you already know that we inherit genes
from our mom and dad, but do we also inherit
from our parents the epigenetic marks that
can silence these genes?
That is the controversial claim known as "transgenerational
epigenetic inheritance", meaning the transmission,
across many generations, of these epigenetic
factors.
Some scientists are saying they have evidence
that pregnant women who go through periods
of mass hunger or traumas like surviving the
Holocaust, that this affects not just the
baby's epigenome (which would make sense),
but the grandchildren as well, all the way
down the family line.
And this runs counter to what we know about
epigenetics: traditionally, we recognize that
these marks are erased twice, first when the
sperm and eggs are made, and again in the
early stages of the embryo, like someone punching
a big old RESET button twice in a row.
So what do we make of a paper like this that
seems to offer proof that the reset doesn't
happen?
Well, here's what this particular paper actually
shows and, warning, you may need to be an
intellectual downhill skier to follow this
double-black diamond ski slope:
It claims that grandma, before she was an
adult, lived through a sharp change in food
supply, and that this effect was passed down
first to her sons, not her daughters, and
then from those sons to their own daughters,
but not their sons, and this led to an increase
in death from heart disease.
So, again, this effect goes from grandma on
your dad's side... through dad, who is unaffected,
and finally to you, if you're a woman, but
not if you're a man.
This is not that different from my own study
that shows that if your sister's grandpa's
mistress was a smoker, your aunt-in-law's
second great-cousinephew might have a persistent
cough at the age of 50.
Kevin Mitchell, a professor of genetics and
neuroscience at Trinity College Dublin, has
a sobering assessment of this study, not mine
but the double-black diamond ski slope one.
He writes that studies like this one, that
seem to show evidence for the transmission
of epigenetic marks across many generations,
all suffer from similar problems.
They are done with very few people, the scientists
test so many things that something is bound
to come up positive, and the scientists usually
go in there wanting to find something as opposed
to wanting to test a specific hypothesis.
This is known as "researcher's degrees of
freedom", and it's the equivalent of a poker
player suddenly deciding that the five completely
different cards she holds are actually called
"The Hand of Genghis Khan", which can beat
five royal flushes!
You can't change the rules of the game, Belle!
You can't!
Transgenerational epigenetic inheritance may
turn out to be the psychoanalysis of biology:
it's a great way to blame relatives for all
your problems but it may not stand up to close
scrutiny.
Epigenetics, as a whole, is very real and
fascinating.
There are even cancer drugs, like azacitidine,
that work at the level of the epigenome.
But here's the lay of the land.
In one corner, we have actual scientists producing
flawed studies and debating amongst themselves
which studies deserve to be taken seriously
and influence our knowledge.
These exchanges are healthy and they represent
science in action.
In the other corner, we have this:
[VIDEO OF DEEPAK CHOPRA]
And
if
this sounds familiar, it's because we have
been through this with quantum mechanics and
stem cells.
Deepak Chopra and his posse are like kids
the week before Christmas.
"Daddy!
Daddy!
Can I open my gifts now?
No?
Mommy!
Mommy!
Can I open my presents now?
I want my epigenetics NOW!"
And that's a trend that we all have to learn
to recognize: when a science is new, unqualified
wellness gurus and swindlers alike will use
early research results to give you lifestyle
recommendations.
And, sure, eating more veggies is a good thing
for your health, and reducing stress levels
does have some impact on your epigenome, but
you don't need to invoke the power of epigenetics
for these recommendations to be valuable.
Our knowledge of what influences our epigenome
and how *we* can change the ways in which
our genes are expressed is comparable to that
map Christopher Columbus allegedly consulted:
sure, this vaguely looks like the Old Continent,
but the details are really questionable, such
as this notice that, "Here is seen the orca,
a sea monster that is like the sun when it
shines, whose form can hardly be described,
except that its skin is soft and its body
huge."
And this is where we are with epigenetics.
Bold explorers are mapping it out, arguing
with each other, developing better tools to
gain precision and accuracy.
Meanwhile, Deepak Chopra's friend Bruce Lipton
decides to leave the map altogether and try
to explain Jesus' miracles with epigenetics:
[VIDEO]
JONATHAN LIKED SOMETHING
My recommendation this week is a blog post
from Dr. David Gorski, a surgical oncologist
and skeptic, entitled "Epigenetics: It Doesn't
Mean What Quacks Think It Means".
He provides more detail on the actual mechanisms
of epigenetics, like DNA methylation, and
surveys how people like Bruce Lipton and Joe
Mercola misuse this area of research to sell
you false self-empowerment.
This blog post was published on Science-Based
Medicine, of which Gorski is the managing
editor, and the entire website is recommended
for anyone who wants to know more about the
issues and controversies in the health sciences,
including regular commentary on quackery.
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