We might all look more or less the same, but there are certain rare body features that
few people across the globe have.
What are they?
From extra body parts to heightened senses, these are some of the rarest body features
found in the world.
Most people have 12 pairs of rib bones equaling 24 total ribs.
However, there's a chance that some people actually have 25 ribs.
One in 200 people have a rare body feature that's called a cervical rib.
According to an article from the Department of Surgery at New York’s Flushing Hospital,
"A cervical rib is present at birth and it forms above the first rib, growing at the
base of the neck, just above the collarbone.
You can have a cervical rib on the right, left, or both sides."
It's possible you have one and don't even know it.
“I don’t believe you.”
This is because this extra rib doesn't always form completely and may just be, quote, "a
thin strand of tissue fibers" that wouldn't even be present on an x-ray.
It may sound concerning, but cervical ribs are usually no big deal.
If the rib puts pressure on blood vessels and nerves — a condition called thoracic
outlet syndrome — it can be painful.
Thankfully, it's treatable.
You probably don't think twice before filling out your eye color on a form, but this seemingly
simple question becomes a lot more complicated for someone with heterochromia, a rare body
feature.
Derived from the ancient Greek words "heteros" meaning different, and "chroma" meaning color,
a person, or animal, with heterochromia has a difference in eye color.
Three types of this condition are known to exist: complete, central, and partial.
A person with complete heterochromia, like Alice Eve, has two different colored eyes,
like one brown eye and one blue eye.
Two different colors in the same iris is considered central heterochromia, which Paris Hilton
has.
Lastly, partial heterochromia means just a part of the iris is a different color from
the rest.
Kate Bosworth has this one.
Heterochromia is most often genetic, but it can also occur as a result from various medical
syndromes or even an eye injury.
The condition — whether acquired or genetic — is extremely rare.
In the United States, fewer than 200,000 people have it.
Natural red hair is rarer than you'd think.
In Red: A History of the Redhead, Jacky Colliss Harvey revealed that
"Worldwide, it occurs in only 2 percent of the population, although it is slightly more
common [...] in northern and western Europe, or in those with that ancestry."
Red hair is recessive, Harvey explained, writing:
"In the great genetic card game, the shuffling of the deck that has made us all, red hair
is the two of clubs.
It is trumped by every other card in the pack."
In order to have a child with this hair color, both parents need to possess the gene.
In the United States, it may not seem like red hair is all that unusual.
However, that may be because a disproportionate amount of redheads are featured in American
advertisements.
While redheads only make up a tiny part of the population, one study found that 30 percent
of ads feature the hair color.
Plus, when you factor in people who've dyed their hair red, you can see how we've all
been bamboozled into thinking this rare body feature is commonplace.
Only 0.6 percent of the American population has the AB-negative blood type, but that isn't
even the rarest type in the world.
According to the Australian Academy of Science, Rhnull — blood that entirely lacks Rh antigens
— is much rarer.
In 1961, an indigenous Australian became the first person discovered to have the blood
type.
Since then, only about 40 additional people have been identified as having the blood type,
making it a truly rare body feature; so rare that there are only nine active donors.
Because Rhnull is compatible with other rare blood types in the Rh family, researchers
and doctors have recognized its value.
Some scientists have even called it “golden blood.”
Although blood donors are kept anonymous, some scientists have attempted to locate Rhnull
donors to ask them for their blood directly.
Golden blood, indeed.
While many Americans may be trying to keep their cholesterol under control, some will
never have to worry about it.
Those folks have a mutation of the PCSK9 gene.
The U.S. National Library of Medicine explains,
"[This gene] provides instructions for making a protein that helps regulate the amount of
cholesterol in the bloodstream."
When this gene is mutated in a particular way, it keeps bad cholesterol very low.
When one woman realized she possessed the rare body feature that renders her incapable
of developing high cholesterol, she said she "really didn't understand" it.
She later told Nature.com,
"[Now] I'm watching ads on TV [for cholesterol-lowering drugs], and it's like, 'Wow, I don't have
that problem.'"
According to The New York Times, only one other person has a, quote, "double dose of
the mutation" — one that was inherited from both parents.
However, 2.5 percent of black people have since been found to have a singly mutated
PCSK9 gene and 3.2 percent of white people have a slightly singly mutated single gene.
Both of these abnormalities help to regulate cholesterol, albeit not as effectively as
a double mutation.
Our ability to see color is all thanks to cells in our eyes called cones.
Typically, people have three types of cones to help them communicate with the brain and,
therefore, see colors.
However, researchers believe there's a percentage of people called "tetrachromats" who actually
have four cones.
These people would be able to see 100 million different colors.
Neuroscientist Gabriele Jordan of Newcastle University spent years searching for tetrachromats
and, in 2010, finally found someone who fit the bill.
In subsequent years, more people — interestingly all women — were discovered to see colors
that many of us are unable to decipher.
The condition may, in fact, be unique to women.
Superior color vision sounds pretty magical, but it's not always a fun experience.
Tetrachromat Concetta Antico admitted to BBC Future,
"The grocery store is a nightmare.
It's like a trash pile of colour coming in at every angle."
Despite seeing so many colors, Antico admitted that white is her favorite color because,
quote, "it is so peaceful and restful for [her] eyes."
With magnetic false lashes, we can all have lush, layered eyelashes.
People with distichiasis, though, already have this.
The rare body feature distichiasis is, according to the American Academy of Ophthalmology,
"A condition in which an extra row of eyelashes emerges from the ducts of meibomian glands."
It results from a genetic mutation of the FOXC2 gene.
In fact, Elizabeth Taylor had this mutation to thank for her voluminous lashes.
In the biography Elizabeth by J. Randy Taraborrelli, Taylor's mother took the diagnosis in stride,
saying, quote, "Well, now that doesn't sound so terrible at all."
Before you get too jealous of people with this rare double row of lashes, though, you
should know it comes with a rather unattractive issue.
“There’s just one small problem.”
Aaron Fay, an ophthalmic plastic surgeon at Massachusetts Eye and Ear Infirmary in Boston,
says that
“A hair grows where there is supposed to be an oil gland on what's considered the wet
part of the eyelid.”
This can cause tearing, eye irritation, and, in some cases, negatively impact a person's
vision.
Maybe this condition isn’t such a gift after all.
“That sucks.”
Science has shown that genetics play a role even in taste buds.
Only about 25 percent of the population can be categorized as what researcher Linda Bartoshuk
dubbed, “super-tasters.”
These super-tasters have more visible taste papillae — tiny dots on the tongue — than
non-tasters.
This rare body feature makes them more sensitive to the taste of certain foods — like those
that are bitter, sweet, or salty.
Because super-tasters also have more pain receptors than non-tasters, they generally
do not like spicy food.
“Mama mia, that’s a spicy meatball.”
They're also less likely to smoke and don't typically like alcohol.
Unfortunately, though, they also don't tend to like vegetables.
This is because veggies often have a bitter taste.
“Like you?
Who the hell said I got to like you?”
Nevertheless, The Nutrition Source explained that super-tasters, especially those who are
women, quote, "tend to have superior cardiovascular profiles" and a lower BMI.
Considering super-tasters also don't love sweet and fatty foods, these things may very
well be linked.
Chances are you have an innie belly button.
Believe it or not, the science of belly buttons was actually studied by real human people.
Jiri Hulcr, a postdoctoral research assistant, along with a group of scientists at North
Carolina State University, founded the Belly Button Biodiversity project and studied belly
buttons.
Of all the participants who took part, only four percent reported having an outie.
Barry Eppley, an Indiana-based plastic surgeon, told Everyday Health that several things — from
the belly button itself to the fat beneath it — determine which kind of belly button
you'll end up with.
Although this means you don't get to choose between an innie and outie, some have turned
to plastic surgery to get their, quote, "ideal" belly button.
Richard Chaffoo, president of the San Diego Plastic Surgery Society and chief of plastic
surgery at Scripps Memorial Hospital, also told Everyday Health,
"The popularity of low-rise jeans and midriff tops has lead to an enormous increase in the
number of requests for belly button revision surgery in the past few years."
Most of the people opting for cosmetic belly button revision surgeries, or umbilicoplasties,
go from outies to innies.
Apparently there are people who don't have to stress over their calcium intake.
“Hold on, let me get some milk.
MILK!”
People with a mutation in the LRP5 gene have high bone density and, as such, aren't at
risk of developing osteoporosis.
According to a study published in The New England Journal of Medicine, the very few
people identified as having the mutation experienced only one negative symptom: difficulty staying
afloat while swimming.
While the initial study of the mutation focused on an especially dense family from Connecticut,
it wasn't long before scientists discovered other extended families with the same genetic
mutation.
Richard P. Lifton, chair of the Department of Genetics, told Yale Medicine Magazine,
"If there are living counterparts to the [hero] in Unbreakable, who is in a terrible train
wreck and walks away without a single broken bone, they're members of this family.
They have extraordinarily dense bones and there is no history of fractures.
These people have about the strongest bones on the entire planet."
Their bones are so strong, in fact, that scientists began attempting to create a drug similar
to the mutation in an effort to treat and even prevent osteoporosis.
Wisdom teeth may have once been important, but, these days, they're kind of just a pain.
Southern Illinois University's Robert Corruccini told New Scientist that when third molars
-- aka wisdom teeth -- try to break through the gums, they often run out of space.
This can lead to them becoming impacted.
With our mouths unable to solve the issue of overcrowding themselves, we turn to oral
surgeons to rip those "wise" teeth out.
While not everyone will need extractions, an estimated 5 million people will go through
the surgery each year.
Some opt to get their third molars taken out before they have time to become a problem.
Ray White, an oral surgeon at the University of North Carolina, told Vox,
“You might not have symptoms now, but you can't assume it's gonna be that way for the
rest of your life.”
Interestingly, though, there are people that won't need to think twice about their wisdom
teeth.
Why?
Simply because they don't have them.
An estimated 35 percent of the population lack wisdom teeth altogether, making it a
rare body feature... or lack thereof.
Now that makes us jealous, and probably makes dentists a little sad.
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