Why can’t we clone human beings and why don’t we have them yet? Well we can and
we do.
Now, I'm not talking about a tricky Orphan Black-style cloning program here, I'm
talking about what nature already does: identical twins.
Identical twins are nature's clones, and have been used as insights into genetics for nearly
150 years. In fact, one of these twin studies just passed overhead
in the International Space Station. Astronaut Scott Kelly is currently spending an entire year in space
to figure out how microgravity and radiation affect the human body, as comparison to his twin and fellow astronaut, Mark Kelly.
So how does nature make a human clone?
Identical twins are, more technically, monozygotic twins. So it's time
for a little birds and the bees. When two people love each other very much… just kidding.
Monozygotic twins means one zygote, or one fertilized egg. And for whatever reason we aren't exactly sure
it could be random, this zygote eventually
splits into two different cell bundles, each will form its own embryo with the same DNA code.
Well how many identical twins or human clones are there in the world?
Well it varies depending on population but it could be anywhere from 3 in a 1000 births
to 30 in a 1000 births. We're not really sure why it happens.
But for all their similarities, identical twins aren't as identical as we once thought.
For example, take my friends Randy and Jason Sklaar here from PBS' new science series "You're Doing
It Wrong." They share the exact same genetic code and would be the perfect candidates for a twin study design… probably.
[Randy] Well we actually were part of a twin study. Years ago...
[Jason] We were like 12 I think?
[Randy] We went to Washington University in St. Louis where we were
and they sat me down in one room and sat Jason down in another room
And I was supposed to look at a picture and then telepathically send it to him
And he was supposed to draw it
[Kyle] Wait so it was kind of like a paranormal twin study?
[Jason] It was... can we, do we have like
[together] telekinesis
[laughter]
[Kyle] But you just said it at the same time though
[Jason] But we didn't mean to
So I'm sitting in this room and I'm staring at a blank page
and the little light comes on when he's staring at the picture
and I'm supposed to know what to draw
Not only did he not draw what I was thinking of
I drew not even remotely, the shapes weren't even similar
[Randy] It was so bad that they shut down the entire experiment
[Jason] I think they lost funding
[Randy] They lost funding because of that!
[Kyle] So you guys are fine examples of nature's clones if I do say so myself,
but what do you think about creating clones unnaturally?
[Jason] Scientifically
[Randy] See that scares us
Cause we successfully cloned a female sheep, Dolly the sheep.
[Jason] Almost 20 years ago
[Randy] Yeah we successfully cloned from the cell of another sheep
Uh, then we have heard nothing about it
[Jason] Like the general public hasn't heard anything about cloning
[Randy] The silence scares me
That means they've definitely cloned people
[Jason] Oh yeah they've cloned people
[Kyle] No, it's gotten much worse underground
[Randy] And all, well you say underground because i believe that an entire clone city lives underneath the Denver airport
[Jason] WHY IS THAT AIRPORT SO FAR AWAY FROM THE CITY?
[Randy] I don't knowww
[Jason] There's no reason!
[Kyle] Must be clone army
[Randy] That's right
[Kyle] Identical twins like Randy and Jason are scientifically significant because they can serve as their own control group
They can help us tease out some of these big "nature vs. nurture" questions
[Randy If genetics remain constant, then any differences between Jason and I can show
the power that the environment has.
like the different hats we're wearing.
[Jason] If Randy and I are leading very different lives
but we have very similar medical histories
that shows the power that genetics has...?
Is it has or have?
[Randy] It's have
[Jason] I'm pretty sure it's has
[Randy] No, it's have
[Randy] I think it's have
[Jason] It's has
[Kyle] Oook, ok, ok, yeahyeahyeah. It doesn't matter.
It's fine, it's fine
In the decades we've been studying identical twins, things have gotten a little bit more...complicated.
We now know that identical twins aren't identical.
During development, mutations arise in the DNA, which means that "share 100% of the
DNA" thing is kind of a generous rounding up, if anything.
And like how epigenetics, or environmentally triggered changes to genes,
can transform Bruce Banner into the Hulk, environmental pressures can change and affect identical twins genomes
This means that a lot of the data we get from twin studies, from the genetic components
of sexual orientation to the possible environmental triggers of schizophrenia, could be hiding
deeper insights, or nothing
We still are studying identical twins, human clones, and learning where the nature vs nurture
line lies or if there even is a line. But genetics has advanced so much in the last few decades and that it seems
to have finally caught up to what identical twins have been saying for basically ever
what makes us who we are really is more than skin deep. Why? Because science!
So a big thanks this week to Randy and Jason Sklaar, the Sklaar brothers
who have a new science show on PBS digital
Why don't you guys tell us a little more about it?
[Randy] It's called "You're Doing It Wrong"
There are a lot of things we do on a regular basis
that I'm sure you will enjoy that basically we're doing it wrong.
We're eating wrong, we're pooping wrong, we're storing our food wrong, we're twerking wrong
[Jason] We're curing colds wrong
[Randy] We're curing hiccups wrong
[Jason] We're running wrong, we're sleeping wrong
[Randy] So we are here to tell you basically how we're doing it wrong
what was the history of how
[Jason] How did we get to start doing it wrong
[Randy] And then how can we do it right?
[Kyle] Fantastic! Guys head over to YouTube at PBS Digital and go check it out
It gets my seal of approval
Want more science? Head back to Nerdist.com and check out my video on the science of Spider-Man's web shooters
And as always, if you have any comments or questions, hit me up on Twitter @Sci_Phile
Thanks!