From identifying mummies to finding new species, here are 10 of the most amazing discoveries
revealed by DNA….
10.
Finding a Murderer
Nowadays we think of DNA testing as an integral part of identifying murderers, but the ability
has only been around for just over 30 years.
In the 80's the idea of genetic fingerprints was unheard of- that was until a murder case
was solved by using this innovative technique- and it changed investigations forever!!
Originally having been developed as a way to determine paternity, molecular biologist
Alec Jeffreys was asked to use a DNA test to verify a confession that had been made
by a 17-year-old boy for two graphic murders that had been committed in England.
The test showed that the boy was not, in fact, responsible for the crimes, and police continued
to look for the true suspect.
They took DNA samples from all of the men who fit a certain profile in the area- a highly
controversial move- and finally found the true culprit, who was confirmed to be the
killer by a DNA test as well.
The following year saw the first conviction in a US court by using the technique, and
it’s now a go-to method for prosecutors in a number of crimes.
Having DNA evidence has helped to not only put the right people away but also to get
innocent people out.
9.
Mummy Identity
In 1940, an ancient skeleton, known as the “Spirit Cave Mummy” was found in a cave
in the Great Basin Desert in Nevada.
Those who unearthed it knew that this find was an important discovery, but it would be
decades until scientific techniques were developed to find out more about it.
First came in the '90s, when radiocarbon dating techniques found the remains to be 10,600
years old- by far the oldest naturally formed mummy to ever have been found.
But this didn't explain who she was and, to do that, scientists were finally able to sequence
her DNA.
She was found to be closely related to the Fallon Paiute-Shoshone Tribe, who have long
laid claim to the cave she was found in as a part of their ancestral lands.
This genetic research was conducted alongside a number of other remains that have been found
across the Americas, and the results are helping researchers understand the movements of human
throughout the continent as they spread during the ice age.
8.
The Recipe for Milk
Milk is something we all take for granted- after all, it’s available in virtually every
food or drink store in the world.
Despite its prevalence, though, milk is actually a very complex liquid, and it was only recently
that genetic sequencing was able to explain how it’s made.
Milk provides all of the essential nutrients needed for the development of the young, and
is a mixture of various components- each with a specific role, such as complex sugars to
aid brain growth, and substances to help protect from infections.
Every mammal produces milk, the glands that produce it are similar across species, but
the milk each one produces is perfectly matched to the needs of their own young.
This, scientists have discovered, is because there's very specific instructions within
the DNA about how the milk should be produced.
There are genes to control protein growth, ones that control fatty acids and sugars,
and ones that oversee the entire process.
By understanding exactly how milk is formed, it's possible that, soon, scientists could
make artificial milk in a lab.
This could someday become the norm- eliminating people's risks of allergies, and with nutrients
that are perfectly mixed for each of us.
7.
Identifying Smugglers
The ivory trade is one of the biggest contributors to the decline in numbers of elephants around
the world, and the high prices people are willing to pay for it means that, despite
it being illegal, it's estimated that as many as 40,000 African elephants are killed each
year solely for their tusks.
With a population of only 400,000, the need for action is greater than ever.
As part of the fight back, scientists are now using DNA testing to trace the origin
of ivory back to the region it came from, and even the port that it was transported
from.
This is because the cartels that are responsible for selling ivory across the world quite often
use techniques, such as falsified shipping manifests and sending the ivory through numerous
ports before reaching its destination, to evade capture.
By determining where the ivory comes from, authorities then have far more information
to help link back to who was responsible for its transport, and the poaching of the elephant,
and hopefully capture and prosecute more offenders.
6.
Triple Hybrid Bird
In May of 2018, a Pennsylvania local spotted an unusual looking bird in his backyard.
He took photos and videos of it, and then realized something strange- it looked like
both a Golden-winged Warbler, and a Blue-winged Warbler, and was singing like a Chestnut-sided
Warbler.
After seeing the bird a few times, he contacted the Fuller Evolutionary Biology Lab, who sent
someone to take blood samples.
When the results came back, they confirmed that the man's suspicions had been right-
this was actually a hybrid of all three bird species that he had seen traits of.
The hybridization between these three species had never been recorded before, and shed new
light on how different warblers interact.
It's also thought to be a sign that reducing populations of each warbler species contributed
to this happening because the females are being forced to look beyond their own communities
to find a mate.
5.
The Tigrina
The improvement in genetic profiling techniques, as well as the way that more animals are being
tested than ever, means that scientists are quite often discovering new species, and learning
far more about the ones we thought had already been identified.
The Tigrina, also known as the oncilla, in Brazil is a great example of this.
These house cat sized felines live throughout the country, and prey on small mammals, lizards,
eggs, and birds- mainly at night.
Tests showed that, what was once thought to be one species, was, in fact, two distinct
ones- although looking very similar to each other.
The two genetic lines separated about 100,000 years ago, and they are now so different that
they don't breed with each other.
The new species, which lives in the Atlantic forest of southern Brazil are now known as
‘Leopardus guttulus’, and the others, found in northeastern Brazil, are called ‘Leopardus
tigrinus’.
4.
Debunking Alien Theories
In 2003, in an old mining town in the Atacama desert, a small skeleton was found, wrapped
in white cloth and tied with a violet ribbon.
It was extremely unusual- it was about 6 inches tall, with the features of a 7-year-old child,
but only had 10 pairs of ribs- as opposed to the 12 found on humans.
Furthermore, the skull was elongated into a cone shape.
The strange appearance of the skeleton has, unsurprisingly, piqued the interest of those
who believe aliens have visited our planet, and they started to believe that these were
the remains of an otherworldly visitor.
In 2018, though, scientists revealed the results of DNA analysis they had performed on the
skeleton.
They had found that it was, in fact, human, and was a girl who was either stillborn or
died immediately after birth..
Her DNA closely resembled that of people from Chile, but she was found to have mutations
in 7 of her genes.
These had caused the skeletal malformations and accelerated their development, and also
gave her a congenital diaphragmatic hernia which is an often seen birth defect that prevents
the proper formation of a diaphragm.
3.
Panda Ancestor
In 2014, a team of paleontologists were searching a cave in China in search of remains of an
ancient ape species.
They returned that day with a collection of bones, none of which were from the ape, but
what they did find was the lower jaw of an ancient panda that lived around 22,000 years
ago.
Within the edges of the bone was enough DNA to test, in what is the oldest sample of panda
DNA to have ever been found.
The evidence showed that this animal belonged to a previously unknown lineage of panda bears
that had split from other species about 183,000 years ago.
They were specifically adapted to living in a subtropical climate- proof that pandas once
lived across a much wider range of habitats than they do today.
Other panda remains have also been found as far away as Hungary and Spain, and researchers
are hoping that further genetic testing can help uncover quite how far around the world
the creatures once lived, and why they are now so limited to three provinces in China.
2.
Food Contents
When we buy food at a store, we check the labeling to see what's in it and take that
as the truth.
The thing is, due to the way that meat is processed, there's a good chance that what
you think you're eating may not be the full story.
In 2017, some pretty startling results were released by the Food Standards Agency in the
UK, which will make you re-think the way you approach your food in the future.
They used DNA tests to determine the origin of meat within 665 samples that had been taken
from restaurants and markets.
They found that 145 of them were partly or wholly made up of unspecified meat- that’s
about 1 in 5!
They also found that some samples contained up to 4 different types of meat, despite only
mentioning 1 in the ingredients, and some contained none of the claimed types of meat
at all.
Meat that was labeled as lamb was most likely to contain meat from other sources, and com
DNA was the most common type of contaminant to be found.
The researchers concluded that these figures weren't possible unless manufacturers were
purposefully substituting the ingredients, which makes you wonder- how often are we eating
things that we don't realize?
1.
Parents of Two Species
There have been a number of different human species, most of whom were thought to keep
to themselves and only breed within the same group.
But recent evidence has shown that things weren’t quite that contained, and that inter-breeding
was quite common.
Scientists tested a 90,000-year-old bone, in 2018, and couldn't believe the results.
While it's been suspected for a while that species did mix, there's evidence of other
DNA within our own, no-one had ever found a direct descendant of it happening.
This was about to change because when the genome had been sequenced, it became apparent
that the bone was from a teenage girl who had equal amounts of Neanderthal DNA and Denisovan
DNA.
She was the direct descendant of two species breeding with each other, and concrete proof
of it happening.
Other research has shown that Homo sapiens and other species also inter-bred before we
outlived the others…
So next time you meet someone that you’re convinced is part Neanderthal- then you could
well be right!
Thanks for watching!
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