- Less than 1% of the population
has this crazy rare body phenomenon,
plus all sorts of other wild body anomalies.
Find out just how rare you are.
Parts that don't follow the rules, two different size eyes,
and what the heck's a Gorlin's Sign?
Get ready to find out if you are truly
one of the unique ones, because today,
we are back at it, for round two of breaking down some
of the rarest body conditions and features on the planet.
Alright, let's dive right in.
Number 10 of the photic reflex.
Do you sneeze when you look at the sun?
You may not be alone in this oddity.
It's been said that about one in four people
will sneeze when they are exposed
to direct sunlight, or just a bright light.
In general, it's called autosomal dominant
compelling helio-ophthalmic outburst syndrome.
Don't ask me to say that again.
Although researchers don't really know exactly
why some people have this interesting reaction,
some studies suggest that neurological signals are crossed
between the trigeminal nerve, the thing
that senses facial sensations, and the optic nerve.
The optic nerve, although it has many jobs, is also
in charge of constricting the eye's pupil
to allow light to penetrate to the retina.
Number nine, Anisocoria.
Have you ever been on a date, gazing into someone's eyes,
and thought to yourself,
Do they have two different sized pupils?
Our next uncommon feature can be a rare thing
that you are born with,
or a sign of something seriously going wrong.
It's called Anisocoria, aka two different sized pupils.
The pupil is actually the part of your eye
that allows light to enter in so that you can see.
About 20% of the world's population has Anisocoria,
or one pupil that is larger than the other.
This can be a very small difference, or fairly large.
For some, this condition is super benign,
possibly genetic, or just no big deal.
For others though, Anisocoria could be your body
giving you a sign of something more serious,
and possibly even life-threatening.
Going on number eight, Raynaud's Syndrome.
We've all been exposed to cold temperatures, right?
Our next rare body feature is one that affects some
of you out there, specifically when you are exposed to cold.
It's seen in between five to 20% of women,
and between four and 14% of men.
I even have it myself.
When part of your body, usually the fingers or toes,
are exposed to low temperatures,
they start to turn white, or even blue in color.
It's your body's overreaction to cold or distress.
Smaller arteries that supply blood to the skin narrow.
This limits of blood flow to the affected areas,
which is called a vasospasm.
During an attack of Raynaud's Syndrome,
affected areas of the skin usually turn pale first.
Next, they often change color, and feel cold and numb.
Number seven, a taste aversion.
Have you ever heard of cilantro,
or more specifically, cilantro taste aversion?
Cilantro is an herb from the leaves of the coriander plant.
It's used to cook different dishes,
salads, curries, salsa, soup, et cetera.
I bring this up, not because I'm hungry, which I am,
but rather, because there are a whole lot
of cilantro haters out there, but for a reason.
There is a genetic variant in some of you
watching this video, where the olfactory receptor gene
makes it so that you strongly perceive
the soapy flavored aldehydes in the cilantro leaves.
This cilantro tastes aversion affects
about 9% of the world's population out there.
Number six, Gorlin's Sign.
Alright, let's find out if you're a part
of the 10% of folks.
Stick out your tongue, and try to touch your nose with it.
Can you do it?
If so, you my friend, are part
of the rare few that have the nose
to tongue touching ability called Gorlin's Sign.
To people in the medical field, like myself,
this could be a signal of other things
going on in your body.
For starters, Gorlin's Sign is seen in half the patients
with Ehlers-Danlos Syndrome and systemic hypermobility.
Hypermobility basically means your joints can move
beyond the normal range of motion.
Remember that other medical term I threw out a second ago?
It's called EDS, a group of inherited disorders
that affect your connective tissues,
skin joints, blood vessels, et cetera.
It can cause things like bruising easily, body pain,
heart murmurs, and even rupture to blood vessels.
Not everyone who can do this cool party trick
ends up having EDS.
number five, no wisdom teeth.
Raise your hand if you have no wisdom teeth.
If that's you, just know, I'm jealous.
You, my toothless friends, are part of the elite
35% of people out there that do not have any traces
of their third and final molars.
So why doesn't everyone have the extra chomps
creeping in the back of their mouths?
Well, they are known as vestigial structures.
In other words, structures that have no apparent function,
and appear to be residual parts from a past ancestor.
All this to say, body parts that maybe once
had a greater use, but in our modern life,
don't really serve that great of a purpose.
Over time, humans no longer needed
the extra grinding power that may have once been needed
when our jaw bones were much larger.
Do you have your wisdom teeth?
Let me know in the comments.
Number four, being ambidextrous.
Maybe, just maybe, you're a part
of the super rare 1% that uses
both left and right hands to perform tasks.
The science around this subject is fascinating.
There are several theories out there
as to why people may be ambidextrous.
Number one, genetics.
A 2021 study found seven gene variants associated
with this rare ability, and it's said to be more common
in males than females.
Number two reason, there could possibly be an imbalance
in the coordination of the left and the right hemispheres
of the brain.
A third theory suggests that a good number
of ambidextrous people are actually left-handers,
not truly dual handers, it's just that there is more
of a cultural preference for right-handed folks.
Can openers, for instance, tend to be crafted
more for right-handed people.
Number three rare condition:
Double hair whorl.
Our next rare body feature only accounts
for 5% of the population.
It's called a double crown, or a double hair whorl.
You see, the highest point on the top of your head
is often referred to as the crown.
Your hairs that grow from this point on your scalp
are arranged in a circular formation called a whorl.
For most people, this whorl pattern grows
in a clockwise pattern, while for some others,
their uncommon hair growth whorl pattern
grows in a counterclockwise pattern.
For the super select extraordinary few,
they have not one, but two exalted double crown.
As far as the current research goes,
the hair pattern on the top of your head
doesn't really serve an underlying purpose.
It has been noted that if your parents
or family members have a double crown, you may be
more likely to have this distinct feature as well.
Number two, Distichiasis.
Has anyone ever told you
that you have a nice, lush set of lashes?
I'm talking about an interesting sort
of naturally occurring eyelash type of extension
that happens in about one in about 10,000 people.
It's called Distichiasis.
It is an uncommon condition that results
in not one, but two rows of eyelashes on just one eyelid.
Double rows of eyelashes are usually the result
of a mutation of the Fox-C2 gene that influences
all kinds of tissue development in the embryo.
While the lucky ones, like Liz Taylor,
enjoyed the benefits of her twin set of eyelashes,
for some people with this condition,
it really just results in double trouble.
Symptoms can range from a minor discomfort, all the way up
to eye injury, and corneal complications,
where you may need to see treatment with an eye doctor.
Number one, Dextrocardia.
Picture this, you're a character in a video game,
and you find yourself in a close encounter battle
with some shady villain type.
We're trying to finish you off
with a direct hit to your heart.
Lucky for you, you have a body anomaly,
where that finishing move wouldn't be as effective.
It's called Dextrocardia, and it's a rare heart condition
in which real people are born with their heart
positioned on the right side of the chest,
instead of its normal position on the left side.
Normally, the heart is located fairly central,
beneath the breast bone,
but it does angle or protrude towards the left.
But with those chosen few who have Dextrocardia,
their heart doesn't follow the path,
and paves its own way toward the right side.
So is Dextrocardia dangerous?
In fact, I've discovered a few in my own career.
It didn't cause any other issues for them,
and they've lived a normal, unsuspecting life.
For others, the heart on the right side of the body
can come with other heart and organ defects.
So how rare is your body?
Do you have any of these uncommon abilities or conditions?
If you guys found this video interesting,
make sure you binge watch this entire playlist, right here,
and tell all your friends to subscribe.
Smack that like button,
and turn your bell notifications on, as well.
Sign up for my email list for more cool medical topics.
Thank you so much for watching,
and stay healthy, my friends.