A tribe of blacks with blue eyes. Different eye shells

Dark-skinned blondes are a mystery that geneticists are struggling with April 13th, 2017

A traveler who comes to Melanesia may be truly shocked: only here can one meet a large number of dark-skinned people with blond hair. Scientists have long tried to figure out the reason for this atypical appearance. Researchers of the 19th century said that the hair of the islanders was dyed with coral lime. Others suggested that the hair quickly fades from the tropical sun and the salty sea water in which the locals splash. More clever people suggested that the lightening was due to a diet rich in fish.

Finally, as usual in such cases, there was some discussion about the admixture of European blood.

Melanesia is an island group in Pacific Ocean, which includes New Guinea, Fiji, Vanuatu and other states. Among the inhabitants of the islands, every tenth person is blond. Considering that the population of Melanesians is about half a million, the phenomenon can be called typical and widespread. Interestingly, along with blond hair, Melanesians inherited pitch-dark skin from their ancestors.

The main version that genetic scientists have put forward for several years was heredity. They recalled that the British and Germans lived on the islands in the 19th and 20th centuries and grew coconut plantations here.

In fact, back in the middle of the 20th century, serious anthropologists wrote that blond hair color repeatedly arose independently in isolated populations almost all over the world. Famous blond Australian aborigines, Indians, Evenks, mountaineers of the Caucasus, Atlas and Hindu Kush. The influence of European admixture was reasonably rejected in all these cases, and the appearance of relatively fair-haired populations was associated with founder and bottleneck effects (see about them on our portal). European blonde is unique only in its huge range and high frequency of occurrence.

However, it is one thing to talk about genetic-automatic processes, and another to discover a specific gene responsible for lightening hair. This is what I did international group geneticists. The case of the Melanesians is remarkable in that they have only two hair color options: black and white. Therefore, the researchers immediately assumed the presence of only one simple mutation in one gene. All that remains is to find her and confirm her guess. To do this, it was necessary to collect saliva and hair samples from 1,209 islanders. Of this wealth, however, only 43 “blonds” and 42 “brunets” went into business - the grants are also not rubber. The justification for the article, of course, was found to be more solid: they say, since all the phenotypes are literally one or two in number, is it worth spending extra effort?

Among the islanders, 10% are blonde, but 26% have a recessive mutation of the protein synthesis gene that determines hair pigmentation. The result has already been tested on 918 Melanesians of the Solomon Islands and 941 residents of other parts of the planet. The “Solomon” mutation turned out to be simple, but is not found anywhere else in the world. The notorious ubiquitous Vikings of Thor Heyerdahl apparently sailed past Melanesia (in a hurry to Easter Island or South America?); on the other hand, the Melanesians also did not particularly disperse from their tropical paradise.

In Europe, blonde hair color is usually determined by a whole combination of genes, but in the Solomon Islands, blondes are distinguished by a single gene, TYRP1, located on chromosome nine.

Such a gene mutation does not occur in Europe; it is a unique feature of the Melanesian population. In general, the structure of the human genome turns out to vary greatly among different populations - the same properties can be encoded by different genes.

Well, the assumptions made more than half a century ago were brilliantly confirmed. Blonde hair is different from blond hair! Isolation and polymorphism work wonders. All that remains for geneticists is to analyze the genes of the Kabyles, Mandans, Arandas, Evenks and Hanzas...

Interestingly, scientists explain the large number of blondes by the fact that for men, blonde women are more attractive, and most often marriages are concluded with them.

Unlike light hair color, blue eye color in all people is explained by one and only gene mutation, which occurred at some point between the 8th and 4th millennia BC. All blue-eyed people on the planet have a common ancestor who lived in those times. Before blue eyed people it simply didn't exist.

Here we looked at the ideas of racists who linked the talent of people and entire nations with the color of their skin and eyes. However, since those times science has stepped far forward, and if in the 19th century. external signs person seemed unchanged, then genetics says that all a person’s data changes through mutations affecting his genes.

In nature, there is such a thing as albinism (from the Latin albus - “white”) - when, due to a disruption in the production of the melanin pigment, which is responsible for the color of the skin, hair, and iris, animals are born “discolored.” This phenomenon can be observed in the most different types animals (penguins, crocodiles, lions, etc.).

Sometimes such individuals are born to dark-skinned people (whether African blacks or American Indians) - in appearance they are absolutely similar to their parents, only the skin and hair are pale white. And their eyes are blue. As Alexander Verzin, head of the scientific and experimental department of the State Institution MNTK “Eye Microsurgery” named after Academician S. N. Fedorov, noted: “Blacks with blue eyes are found, but extremely rarely. And usually these are albino blacks who also have light skin.”

In the book “Peoples. Races. Cultures,” written back in 1971 jointly by the famous anthropologist N. N. Cheboksarov and biologist I. A. Cheboksarova, it was noted: “Many human characteristics, including racial characteristics, arose through mutations.

For example, there is reason to believe that our ancestors had relatively dark brownish skin, black hair and Brown eyes, which are still characteristic of most races. The most depigmented racial types are blondes with bright eyes— most likely appeared through mutations, concentrated mainly in Europe off the coast of the Baltic and North Seas.”

For a long time, this assumption remained a hypothesis, which nevertheless caused furious convulsions of racists of all stripes.

And then, at the beginning of 2008, scientific confirmation followed. “A group of scientists from the University of Copenhagen discovered a genetic mutation that took place 6-10 thousand years ago and is the cause of the eye color of all blue-eyed people now living on the planet.

“Originally we all had brown eyes,” says Professor Eiberg from the Department of Cellular and Molecular Medicine. "But genetic mutation"affecting the OCA2 gene on our chromosomes created a 'switch' that literally 'turned off' the ability to form brown eyes."

The OCA2 gene encodes the so-called P protein, which is involved in the production of melanin, the pigment that gives color to our hair, eyes and skin. The "switch" that is located in the gene adjacent to OCA2, however, does not "turn off" the gene completely, but rather limits its action to reducing the production of melanin in the iris - and brown eyes "turn" blue. The "switch" effect on OCA2 is very specific. If the OCA2 gene were completely disrupted or turned off, people would have no melanin in their hair, eyes or skin at all - a phenomenon known as albinism."

The eyes of a mother and son from the Burusho tribe in northern Pakistan.

Professor Eyberg is a famous scientist, author of more than 250 scientific articles, has been working on this problem since 1996. A detailed report by Danish scientists on their research was published in the authoritative scientific journal Human Genetics.

At the end of the article it is noted: “Mutations responsible for Blue colour eyes most likely occurred in the Middle East or in the area northwest of the Black Sea region, a significant movement of occupation agriculture population from where to Northern Europe took place in the Neolithic, approximately 6-10 thousand years ago." (By Middle East, Eibert means northern Afghanistan, where the blue-eyed Kalash now live; “this place could be the northern part of Afghanistan,” he told reporters from the British newspaper Telegraph.

Both the date and location of the mutation are, of course, speculative - they are not recorded in the genes in any way. When the place of mutation that led to the appearance of blue-eyed blonds is called Northern Europe, the shores of the Northern and Baltic seas or the mountains of Northern Afghanistan, this is explained by the presence in these regions of historical time large isolated populations with such a recessive (suppressed by others) genotype.

N.N. Cheboksarov and I.A. Cheboksarova also write about this: “Genetic drift, which caused an increased concentration of recessive mutations of depigmentation of the skin, hair and iris of the eyes, on the outskirts of the ecumene, along with negative selection, played a significant role in the formation of various racial types of light Caucasians (blond) Northern Europe.

Similar processes of concentration of recessive light-colored genes are observed in some isolated populations living in natural geographic conditions that exclude the influence of natural selection on depigmentation.

For example, based on personal observations during the 1924 expedition to Afghanistan, N.I. Vavilov noted a fairly high percentage of people with gray and blue eyes among the Nuristanis (kafirs) - a small Iranian-speaking people living in a remote mountainous region at an altitude of 3- 4 thousand meters above sea level” Vavilov himself noted that “Kafiristan, which embraces a significant part of Afghanistan, is already an ideal insulator in which the most ancient persecuted peoples live to this day.”

N ethnicity in Pakistan, inhabiting the mountains of the southern Hindu Kush.

Germany and Scandinavia too for a long time were the same area isolated from the rest of the world.

Blue eyes, blond hair and White skin didn't help at all cultural development ancient Germans, Libyans North Africa or the Hindu Kush mountaineers, rather, the isolation in which they found themselves (and which ensured that they retained their genotype) led to their severe cultural backwardness.

Cultural, economic and political dominance Western Europe- is by no means a phenomenon of the entire world history, but only a small (in its scale) period from approximately 1750 to 1950, at which time other countries and peoples, be it India or Africa, became the object of its colonial expansion.

Here we looked at the ideas of racists who linked the talent of people and entire nations with the color of their skin and eyes. However, since those times science has stepped far forward, and if in the 19th century. While the external signs of a person seemed unchanged, genetics says that all a person’s data changes through mutations affecting his genes.

In nature, there is such a thing as albinism (from the Latin albus - “white”) - when, due to a disruption in the production of the melanin pigment, which is responsible for the color of the skin, hair, and iris, animals are born “discolored.” This phenomenon can be observed in a wide variety of animal species (penguins, crocodiles, lions, etc.).

For example, there is reason to believe that our ancestors had relatively dark brownish skin, black hair and brown eyes, which are still characteristic of most races. The most depigmented racial types—blonds with light eyes—most likely appeared through mutations, concentrated mainly in Europe off the coast of the Baltic and North Seas.”

For a long time, this assumption remained a hypothesis, which nevertheless caused furious convulsions of racists of all stripes.

“Originally we all had brown eyes,” says Professor Eiberg from the Department of Cellular and Molecular Medicine. "But a genetic mutation affecting the OCA2 gene on our chromosomes created a 'switch' that literally turned off the ability to form brown eyes."

The eyes of a mother and son from the Burusho tribe in northern Pakistan.

Professor Eiberg is a famous scientist, the author of more than 250 scientific articles, who has been working on this problem since 1996. A detailed report by Danish scientists on their research was published in the authoritative scientific journal Human Genetics.

The article concludes: “The mutations responsible for blue eye color most likely occurred in the Near East or in the area northwest of the Black Sea region, a significant movement of agricultural populations from which to northern Europe took place in the Neolithic, approximately 6-6 years ago. 10 thousand years ago." (By Middle East, Eibert means northern Afghanistan, where the blue-eyed Kalash now live; “this place could be the northern part of Afghanistan,” he told reporters from the British newspaper Telegraph.

Both the date and location of the mutation are, of course, speculative - they are not recorded in the genes in any way. When Northern Europe, the shores of the North and Baltic seas or the mountains of Northern Afghanistan are called the place of the mutation that led to the appearance of blue-eyed blonds, this is explained by the presence in these regions in historical times of large isolated populations with such a recessive (suppressed by others) genotype.

N ethnicity in Pakistan, inhabiting the mountains of the southern Hindu Kush.

Germany and Scandinavia have also been a similarly isolated region from the rest of the world for a long time.

Blue eyes, blond hair and white skin did not help the cultural development of the ancient Germans, Libyans of North Africa or the Hindu Kush mountaineers; rather, the isolation in which they lived (and which ensured that they retained their genotype) led to their severe cultural backwardness.

The cultural, economic and political dominance of Western Europe is by no means a phenomenon of the entire world history, but only of a small (in its scale) period from approximately 1750 to 1950, at which time other countries and peoples, be it India or Africa, became the object of its colonial expansion.

About a quarter of the population of Melanesia in the Solomon Islands archipelago has the extremely unusual feature of dark skin combined with blond hair. Located east of Papua New Guinea in Oceania, the archipelago consists of thousands of islands, home to more than half a million Melanesians. They have the darkest skin in the world outside of Africa, but many have blond afros on their heads.

This rarity has excited the minds of scientists and genetics experts long years. Until recently, heredity was blamed for everything: supposedly the gene for “blond hair” was inherited by Melanesians from their European ancestors - the British, Germans and Australians, who owned the islands for hundreds of years. In the 19th century, the islands were under German jurisdiction, in 1893 the islands came to Great Britain, and at the beginning of the 20th century, the British, together with the Australians, grew coconut plantations there.

But locals do not agree with the version about genetics, although it seems reasonable. They insist their blond hair is the result of a fish-rich diet and sun exposure. But both theories are far from the truth. According to a recent study, random mutations may be responsible for the secrets of Melanesian blondes.

Nova Scotia Agricultural College geneticist Sean Miles noted that all Melanesians have the same shade of blond hair. This means that hair color is regulated by genes. Miles and his colleagues decided to find the gene and to do this they took saliva and hair samples from 42 blond islanders and 42 dark-haired Aborigines.

Both groups had completely different versions of the TYRP1 gene, which encodes a protein involved in pigmentation. Hair color is determined by only one amino acid in the protein - arginine instead of cysteine.

25% of the population of the Solomon Islands are carriers of the mutated gene. This means that blondes can inherit their hair color from both parents. Anthropologist from Temple University in Philadelphia, Jonathan Friedlander, noted that the mutation most likely arose by chance in one person. This seems to be true because the indigenous population of the islands was quite small.

Incredible facts

Genes are an amazing and very unpredictable thing. They will tell you things you don't know about yourself.

Sometimes genes produce things that shock us. And we can only be amazed at what surprises nature brings.

There are several thousand genes in the genotype and it happens that they appear very unexpectedly.

For example, twins born may be as different from each other as heaven and earth, or a dark-skinned parent may have a completely white child.

Here's 18 most interesting cases when genes showed yourself in the most amazing way:

How genes are expressed

1. Beautiful Blue eyes

Dominant genes can create unique beauty traits, such as piercing blue eyes that are too good to be true.

Look at this black girl with incredible blue eyes.

Many people think that such beauty is the merit of contact lenses or that the girl uses Photoshop to give this color to her eyes.

Again, many people have misconceptions about typical features every race.

To refute all suspicions, the girl provides evidence in the form of her childhood photographs. The same blue eyes are clearly visible on them, and her mother also has the same eye color.

2. Different eye shells

Do you notice something unique and unusual about this red-haired girl?

Pay attention to her eyes. The different membranes of the eye are caused by heterochromia, a condition in which the eyes have different colors as a result of excess or lack of melanin.

This disease can affect hair and skin.

3. Asian woman with blonde hair

It's a common misconception that all Asian women have long hair. dark hair.

The woman on the right is half Asian and half European. Her almond-shaped eyes and reddish hair look extremely unusual. This unique cultural mix is the result of the unpredictability of genes.

4. Twin brothers, as different as heaven and earth

Some genetic features can cause twins to look like they are from different planets.

Take a look at model Niall DiMarco, who looks so Italian, but his twin brother Nico looks more Irish.

These are the surprises genes sometimes present.

5. Unlikely twins again

Interracial marriages can produce unexpected, beautiful children that will blow your mind.

Believe it or not, these two girls are twin sisters. Lucy on the left has white skin, straight red hair and blue eyes, which she inherited from her fair-skinned father.

But Maria has curly dark hair, brown eyes and dark skin. The girl got this appearance from her dark-skinned mother. This is how genes unexpectedly appeared in twin girls.

6. Dark-skinned blond

Some people dye their hair and wear contact lenses to look beautiful.

The same young man you don't need either one or the other. He is African with light eyes and hair. And nature gave him all this.

The young man is clear proof that blond-haired, blue-eyed Africans exist.

Amazing genes

7. Eyelashes growing in two rows

This rare disorder that causes abnormal eyelash growth is called distichiasis. Rare genetic disease, in which eyelashes grow in 2 rows.

8. White-skinned mulatto

This pretty girl has a European mom and a dark-skinned dad.

9. Such different sisters

When people are two different cultures create a family, a genetic mix can give the most unpredictable results.

It's hard to believe that these two girls are sisters. Their father is European and their mother is from Argentina.

As a result, one sister was born with blond hair and blue eyes, and the other with dark hair and dark skin.

10. Albinos from generation to generation

This is not a Finnish family at all, as it might seem at first glance. They are actually an Indian family.

The unusual appearance of the Pullan family members is explained by albinism, a genetic disorder that has been passed on for three generations.

The disease is caused by processes that reduce the amount of melanin produced.

11. Guy with different colors eyebrows

Poliosis is a disease characterized by partial depigmentation or graying of hair. This guy with the disease looks strange and a little freaky.

Poliosis can affect both hair and eyebrows and eyelashes.

12. Child with poliosis

The girl was born with a white streak of hair, just like her mother.

She is the fourth generation of her family to have this unique trait caused by poliosis.

13. And in this family almost everyone is red.

They say red-haired people may soon disappear altogether. You can't say anything like that when looking at this family.

The only non-red-haired members of the family are the grandmother and aunt.

14. Birthmarks confirming relationship

Remember how in Indian cinema, relatives found each other by birthmarks? Sometimes this happens in real life.

The same birthmarks reveal kinship.

15. White-skinned child with a dark-skinned father

There is no doubt that this is father and son.

But the combination of genes that created this magnificent child decreed that the baby inherited the color of his mother's skin.

16. Guy with a white eyebrow

Genetic conditions such as Waardenburg syndrome can create interesting hair color combinations.

This disease can cause certain facial abnormalities, such as unusual hair pigmentation, different eye colors, or congenital deafness.

17. Matching moles

And sometimes moles can be found in the same places. What is this? Blood relatives or soul mates?

18. Such different sisters

These sisters were born into a mixed marriage and are polar opposites when it comes to looks. Genetics did its best: one of the girls inherited the features of an Italian parent, and the other - an Irish one.

As a result, one girl has fair skin and bright red hair, and the other has dark skin and dark eyes and hair.