Short Stuff: Blaschko's Lines

Did you know you have stripes? It’s true, you just can’t see them. Learn all about these little-known lines today!

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Episode Transcript

Speaker 1 (00:00):
Hey, everybody, it's Josh and Chuck is here in spirit too,
and we just wanted to drop a casual reminder that
we are going to have a swinging Pacific Northwest Swing
this coming February, and tickets are now on sale. February
one will be at the More Theater in Seattle, February
two will be at Revolution Hall in Portland, and on

(00:22):
February three, for SF Sketch Fest, will be at the
Sydney Goldstein Theater. Go check out all of our social
media's for more information and links to tickets, and we'll
see you in February. Hey, I'm welcome to the Shorts
to Find Josh and there's Chuck tally Ho. It's short

(00:43):
Stuff time and we're talking about something that admittedly I
kind of understand and kind of hope you really understand.
I do good. I do. Also, before we started, wanting
to give a hat tip to my wife, you me
who came up with this one said have you ever
heard of this? It's crazy? And I looked into it
and I was like, this is crazy because what you

(01:05):
we found and what we're about to explain to all
of you is that humans are a species. Don't forget
we're animals with stripes. We actually are a striped species
of animal. Did you know that before? I've never heard
of this. I did not know we were all brindle
coated animals like my dog Nico. Yeah, that's exactly right,

(01:26):
that's exactly what we are. We have beautiful patterns of
swirls and whorls and drips and drops and all sorts
of cool stuff all over us, but we can't see
them normally under normal circumstances because we don't see on
the UV side of the spectrum. But if we did,
we'd be like, hey, I like your stripes. Oh, I

(01:47):
like your stripes. And with some people, depending on the
condition they have, they actually their stripes actually show. It's
pretty interesting stuff. But the whole thing we're talking about,
if you noticed, um the title of this episode, or
what are called blash cos lines, those are the stripes
that all humans have. Now did this happen? Because you
mean had a black light and went, oh my god,
I don't know where she turned this one up. I

(02:09):
didn't ask her. I'll have to ask her and then
we'll record a pick up. All right, So hold on
insert answer here. Uh So, blash cos lines that is
in fact a name. Uh. It was named after a dermatologist,
Alfred Blaschko and the nineteen hundreds. He was the first
person to uh notice this basically and write about it. Um.

(02:32):
He thought he was a little bit off though, because
he thought that they followed predefined patterns on humans. Um.
But they don't. And the weird thing is is you
might think is like, all right, so maybe these are
um lines that sort of indicate where your blood vessels
are or your nerve endings are, or your nerves or whatever. Um,

(02:52):
that is not the case. Uh, these stripes are not
blood vessels that you could see under a black light
at all. But we kind of know what it is now,
right right, Yeah, there's no system in the body that
these things follow. Instead, they're their own thing. They seem
to be their own thing, um, and they are distinct
on all people. But there are kind of some general
patterns that we'll talk about. But what what we've come

(03:14):
up with finally today is still today we're not certain
that this is correct, but the general consensus is that
what blash cos lines are evidence of the migratory route
that our skin cells took and then settled into while
we were developing in the womb. Right. Um, I'm just
gonna read this little bit from mental Flass because I

(03:35):
think it kind of sums it up nicely. Yeah. I
thought so too, And we always love to shout out
our our old pals at Mental Flass, the m f fs,
the ms uh. Basically, they said, these are cellular relics
of our development, basically from single cell uh things you
quoting this, No, I'm paraphrasing the beginning. Um, as the

(03:59):
cells of I did, they differentiated, some became muscles, others bones,
still others organs, and some became skin. As those skin
cells continued dividing, they expanded and stretched to cover a
quickly growing body. One cell line pushed and swirled through
another like steamed milk poured into an espresso to make
a latte, and Blash goes. Lines are the molecular evidence

(04:22):
of those swirls. It was very pretty writing. It was.
So the reason that we can see these lines, Chuck,
I think we should talk about after a break. So

(04:57):
the reasons we can see these lines, Chuck, I think
we're you talk about now? Very nice. So, Um, they
believe that the reason that there's differences even though you
can only see them under the UV spectrum. Under normal,
normal circumstances, you cannot see the difference between skin cells
on your arm, or on your shoulder, or on your

(05:20):
torso wherever, and you have blash cost lines all over
your body, as we'll see, because the cells that make
up our skin are almost entirely identical. They all come
from generally the same genetic information, so they all start
out from the same cell or gloves of cells. Like
mental falls pointed out, UM, But because of like the

(05:43):
different minute experiences that each cell has, those instructions get
produced and just slightly different ways, so that um, we
think of ourselves as like genetically monolithic beings. Right, It
turns out the term for humans UM are mosaics. All

(06:04):
of those cells are so slightly different that it's almost
like slightly different colored tiles being put up against one another.
And they're so similar that again, under normal light, you
can't see the difference. But when you put the put
yourself under a black light in a dark room, those
differences show up. That's why they think we're able to
see blash cost lines. That's why they think we have them.

(06:25):
It's the same reason when you look at identical twins.
They're they're actually a little bit different. Is again these
environmental factors that happen when you're a twin and and
in fact, uh, we just did an episode recently, what
was that on just this week on Doppelgangers. Doppelgangers when
they've seen a lot of evidence like when twins are
split up at birth, Um, they end up being quite

(06:47):
a bit different. And it's because of epigenetics. Isn't these
environmental factors. But even if they they aren't broken up,
even if they're together, these twins are these you know,
these minute little jenette differences that end up meaning these
twins are a little bit different. And that's the same
basic concept here. Yeah, but rather than whole people, we're

(07:08):
talking about the difference between genetically identical cells within one person.
There is something else called chimerism. So instead of mosaicism,
this is chimerism. And some people can have different genetic
material within them. So like um, very famously people with
two different eyes, they're chimeras, or they they're chimeric, I

(07:30):
should say, because different genetic information went into constructing each
eye and that's why they have two different colored eyes.
That's extraordinarily rare mosaicism apparently is universal that we're all.
We're just not if you took one cell in another
cell and you could get as granular as possible and

(07:50):
investigating them, you'd see that they're just slightly not the same,
even though they came from the same blueprint. Yeah, there's
a New York Mets picture that has one blue eye
and one dark eye? Is that David Bowie number seventy two.
It's Max Scherzer, And uh boy, it's just I didn't

(08:11):
even notice it until last year. And this is a
guy who's sort of at the latter stages of his career.
But then once you see a picture of this guy,
you're like, oh my god, it's really a striking difference
because it's a very very blue eye and a very
very brown eye. Uh and I just think it's so
cool looking. Yeah, like what a I don't know. I

(08:33):
would just always just go right up to people's faces
and and go, hi, how are you just like freak
him out a little bit? I think it's really cool.
Give him the left side, and then the right side,
and left side and the right side. Yeah. So, like
we said, they're like there, there's kind of some general
rules that like these lines will follow depending on where

(08:53):
you are on your body. Right, Yeah, there's like patterns,
which makes sense because you know all of us sort
of grow generally in the same way as far as
arms and legs and finghies and toes and torsos and
necks and armpits and all that stuff. So depending on
what can we keep naming parts about the dirty parts,

(09:16):
let's start, Um, they're only two. Uh So when you're
looking at a body, like there will be maybe a
V shape down your back, uh and inverted you from
the breast to the upper arm. Your lateral trunk will
have a wave like shape. There might be an S
shape on your abdomen, stuff like that. Yeah, your scalp. Actually,

(09:37):
if you look at your whole head, it looks like
as far as your blash co lines are are concerned,
that you're wearing a ball of clava like around around
your eye areas open, but there's different like lines surrounding
it elsewise, and apparently on your scalp at spirals, whereas
on the side of your face it comes there like
kind of vertical lines. It's pretty cool. There's um, I

(10:00):
think blash Coo himself, did you know, some initial um
descriptions of it through sketches, but since then science has
really kind of gotten pretty good at drawing it. So
there's a lot of neat drawings of blash cos lines
on on the Internet of all places. But was he early?
He was like nineteen o one from what I saw, Okay,

(10:21):
the earliest. But Chuck, I think you should take the
fact of the short stuff, um, that the blash cos
lines don't just exist on the skin, right, Yeah, this
was pretty freaky. Um. Apparently your teeth and eyes and
tongue all have blash cose lines as well. Yeah, which
I mean anything that that forms from cells, you know,

(10:43):
expressing themselves, writing poetry and songs. You mentioned earlier though
about there are certain conditions that someone might have where
these lines are revealed in in regular light with regular vision,
right yeah, yeah, so vital eye where your skin loses
its pigmentation. Um, it often follows blash COEs lines. Um.

(11:06):
Also there's other types of congenital conditions, I believe, and
some inquired ones where um, so vidaigo would be like
a negative of your your blash COEs lines, whereas the
some of the other ones, they're like it's like a
tiger stripes. Like you can see the person's blash COEs
lines because it's hyper pigmented, so you can see them

(11:27):
without UV light. You can just see him under normal
visible light. And it's pretty cool looking, actually, I have
to say yeah, although usually if you look up on
the internet see what this looks like, it's just like
close ups of armpits and stuff. Sure, sure, and I
say it's pretty cool looking. I don't know how you know,
somebody who has a condition where their blash goes lines

(11:47):
are showing all the time feel about it. But as
an observer, I think it's pretty interesting and neat. And
then also when you stop and think about if you're
like that person's skin is striped, your skin is striped
to pal you just don't see it because you have
to see it under normal UV lights. Yeah, pretty cool. Yeah.
So that's it for blash Coast Lines a A thanks

(12:09):
you me and thank you friend for listening to this episode.
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