Incredible powers of people obtained through genetic mutations. Mutation of people

January 2nd, 2016

Vestigial structures and compromise structures can still be found in the human body, which are very definite evidence that our biological species a long evolutionary history, and that it did not just appear out of nowhere.

Also another series of evidence of this are the ongoing mutations in the human gene pool. Most random genetic changes are neutral, some are harmful, and some appear to cause positive improvements. Such beneficial mutations are raw materials that can eventually be used by natural selection and distributed among humanity.

This article contains some examples of beneficial mutations...

Apolipoprotein AI-Milano

Heart disease is one of the scourges of industrial developed countries. It's a legacy we inherit from our evolutionary past, when we were programmed to crave energy-rich fats, then a rare and valuable source of calories but now a cause of clogged arteries. However, there is evidence that evolution has potential that is worth exploring.

All people have a gene for a protein called apolipoprotein AI, which is part of the system that transports cholesterol through the bloodstream. Apo-AI is one of the lipoproteins high density(HDL), which are already known to be beneficial because they remove cholesterol from artery walls. A mutated version of this protein is known to exist among a small community of people in Italy, called apolipoprotein AI-Milano, or Apo-AIM for short. Apo-AIM works even more effectively than Apo-AI at removing cholesterol from cells and dissolving arterial plaque, and additionally acting as an antioxidant to prevent some of the damage from inflammation that typically occurs with arteriosclerosis. Compared with other people, people with the Apo-AIM gene have a significantly lower risk of developing myocardial infarction and stroke, and are now pharmaceutical companies plan to bring to market an artificial version of the protein in the form of a cardioprotective drug.

Others are also produced medications, based on another mutation in the PCSK9 gene that produces a similar effect. People with this mutation have an 88% reduced risk of developing heart disease.

Increased bone density

One of the genes that controls bone density in humans is called low density LDL-like receptor 5, or LRP5 for short. Mutations that impair LRP5 function are known to cause osteoporosis. But another type of mutation may enhance its function, causing one of the most unusual mutations known in humans.

This mutation was discovered by chance when a young man and his family from the Midwest were in a serious car accident and walked away from the scene without a single broken bone. X-rays revealed that they, like other members of this family, had much stronger and denser bones than is usually the case. The doctor involved in the case reported that "none of these people, whose ages ranged from 3 to 93 years, ever broke a bone." In fact, it turned out that they are not only immune to injury, but also to normal age-related degeneration skeleton. Some of them had a benign bony growth on the roof of their mouth, but apart from this the disease had no other side effects- besides, as the article dryly noted, this made swimming difficult. As with Apo-AIM, some pharmaceutical firms are exploring the possibility of using it as a starting point for therapies that could help people with osteoporosis and other skeletal diseases.

Malaria resistance

A classic example of an evolutionary change in humans is a mutation in hemoglobin called HbS, which causes red blood cells to take on a curved, sickle-shaped shape. The presence of one copy confers resistance to malaria, while the presence of two copies causes the development of sickle cell anemia. But we are not talking about this mutation now.

In 2001, Italian researchers studying the population of the African country of Burkina Faso discovered a protective effect associated with a different variant of hemoglobin called HbC. People with just one copy of this gene have a 29% lower risk of contracting malaria, while people with two copies can enjoy a 93% reduction in risk. In addition, this gene variant causes, in the worst case, mild anemia, and not at all debilitating sickle cell disease.

Tetrochromatic vision

Most mammals have imperfect chromatic vision because they have only two types of retinal cones, retinal cells that distinguish different shades of color. Humans, like other primates, have three such species, a legacy of a past when good chromatic vision was used to find ripe, brightly colored fruit and provided an advantage for the survival of the species.

A gene for one type of retinal cone, primarily responsible for blue tint, was found on the Y chromosome. Both other red- and green-sensitive species are found on the X chromosome. Due to the fact that men have only one X chromosome, a mutation that damages the gene responsible for red or green tint, will lead to red-green color blindness, while women will retain a backup copy. This explains the fact why this disease is almost exclusively confined to men.

But the question arises: what happens if a mutation in the gene responsible for the color red or green does not damage it, but shifts the color range for which it is responsible? Genes responsible for red and green colors, this is exactly how they appeared, as a consequence of duplication and divergence of a single hereditary retinal cone gene.

For a man this would not be a significant difference. He would still have three color receptors, only the set would be different from ours. But if this happened to one of the cone genes in a woman's retina, then the genes for blue, red and green would be on one X chromosome, and the modified fourth would be on the other... which means she had there would be four different color receptors. She would be, like birds and turtles, a true "tetrachromat", theoretically capable of distinguishing shades of color that all other people cannot see separately. Does this mean that she could see completely new colors that are invisible to everyone else? This is an open question.

We also have evidence that in rare cases this has already happened. During a color discrimination study, at least one woman performed exactly as one would expect from a true tetrachromat.

We are already talking about an artist from San Diego, she is a tetrachromat.

Less need for sleep

Not everyone needs eight hours of sleep: scientists from the University of Pennsylvania discovered a mutation in the little-studied gene BHLHE41, which, in their opinion, allows a person to fully rest for more a short time sleep. In the study, researchers asked a pair of non-identical twins, one of whom had the aforementioned mutation, to abstain from sleep for 38 hours. The “mutant twin” slept only five hours in everyday life - an hour less than his brother. And after deprivation, he made 40% fewer errors in tests and it took him less time to fully restore cognitive function.

According to scientists, thanks to this mutation, a person spends more time in a state of “deep” sleep, which is necessary for the full restoration of physical and mental strength. Of course, this theory requires more thorough study and further experiments. But for now it looks very tempting - who doesn’t wish there were more hours in the day?

Hyperelastic skin

Ehlers-Danlos syndrome - genetic disease connective tissue, affecting joints and skin. Despite a number serious complications, people with this disease are able to painlessly bend their limbs at any angle. The character of the Joker in Christopher Nolan's The Dark Knight is partly based on this syndrome.

Echolocation

One of the abilities that any person possesses to one degree or another. Blind people learn to use it perfectly, and the superhero Daredevil is largely based on it. You can test your skill by standing with your eyes closed in the center of the room and loudly clicking your tongue in different directions. If you are a master of echolocation, you can determine the distance to any object .

Eternal youth

It sounds much better than it actually is. A mysterious illness dubbed "Syndrome X" prevents a person from ever showing signs of growing up. Famous example- Brooke Megan Greenberg, who lived to be 20 years old and still physically and mentally remained at the level of a two-year-old child. Only three cases of this disease are known.

Insensitivity to pain

This ability was demonstrated by the superhero Kick-Ass - this is a real disease that does not allow the body to feel pain, heat or cold. The ability is quite heroic, but thanks to it a person can easily harm himself without realizing it and is forced to live very carefully.

Superpower

One of the most popular abilities among superheroes, but one of the rarest in the real world. Mutations associated with a lack of the myostatin protein lead to a significant increase in muscle mass a person with no growth of adipose tissue. There are only two known cases of such defects among all people, and in one of them two year old child Has the body and strength of a bodybuilder.

Golden Blood

Blood with zero Rh factor, the rarest in the world. Over the past half century, only forty people with this blood type have been found; at the moment, only nine are alive. Rh zero is suitable for absolutely everyone, since it lacks any antigens in the Rh system, but its carriers themselves can only be saved by the same “golden blood brother”.

Since scientists have been studying similar issues for quite a long time, it became known that it is possible to obtain a zero group. This is done through special coffee beans that are able to remove agglutinogen B from red blood cells. Such a system did not work for a relatively long time, since there were cases of incompatibility of such a scheme. After this, another system became known, which was based on the work of two bacteria - the enzyme of one of them killed agglutinogen A, and the other B. Therefore, scientists concluded that the second method of forming a zero group is the most effective and safe. Therefore, the American company is still working hard to develop a special device that will effectively and efficiently convert blood from one blood group to zero. And such zero blood will be ideal for all other transfusions. Thus, the issue of donation will not be as global as it is now and all recipients will not have to wait so long to receive their blood.

Scientists have been racking their brains for centuries about how to create one single universal group, people with whom there will be a minimum risk for various diseases and shortcomings. Therefore, today it has become possible to “zero” any blood group. This will significantly reduce the risk in the near future various complications and diseases. Thus, studies have shown that both men and women have the lowest risk of developing CHD. Similar observations have been carried out for more than 20 years. These people answered specific questions about their health and lifestyle over a period of time.

All existing data was published on various sources. All studies have led to the fact that people with the zero group actually get sick less and have the lowest likelihood of developing coronary artery disease. It is also worth noting that the Rh factor does not have any specific effect. Therefore, the zero blood group does not have any Rh factor, which can separate one or another group. One of the most important reasons It turned out that each blood also has different coagulability. This further complicates the situation and misleads scientists. If you mix the zero group with any other and do not take into account the level of coagulation, this can lead to the development of atherosclerosis and death in a person. At the moment, the technology of converting one blood group into zero is not so widespread that every hospital can use it. Therefore, only those common medical centers who work for high level. The zero group is a new achievement and discovery of medical scientists, which today is not even familiar to everyone.

But did you know that there is also

It has long been the case that people with genetic mutations were considered monsters and monsters. They frightened children and tried to avoid them in every possible way. We now know that the unusual appearance of some people is the result of rare genetic diseases. Unfortunately, scientists have not yet learned how to deal with them. We present to your attention a selection of the ten most unusual genetic mutations found in people. Fortunately, they are quite rare.

1. Progeria. Occurs in one child out of 8,000,000. This disease is characterized by irreversible changes in the skin and internal organs caused by premature aging of the body. Average duration The lifespan of people with this disease is 13 years. There is only one known case in which the patient reached the age of forty-five years. Was recorded in Japan.

2. Yuner Tan syndrome (UTS). People with this rare genetic defect tend to walk on all fours, have primitive speech and poor brain activity. The syndrome was discovered and studied by biologist Yuner Tan after meeting the Ulas family in one of the Turkish villages. Even a documentary film “The Family Walking on All Fours” was made about this unusual family. Although some scientists are inclined to think that SUT has nothing to do with the work of genes.

3. Hypertrichosis. During the Middle Ages, people with a similar gene defect were called werewolves or apes. This disease is characterized by excessive hair growth throughout the body, including the face and ears. The first case of hypertrichosis was recorded in the 16th century.

4. Epidermodysplasia verruciformis. One of the rarest gene failures. It makes its owners very sensitive to the widespread human papillomavirus (HPV). In such people, the infection causes an increase in numerous skin growths, reminiscent of wood in density. The disease became widely known in 2007 after a video of 34-year-old Indonesian Dede Kosvara appeared on the Internet. In 2008, a man underwent a complex operation to remove six kilograms of growths from his head, arms, legs and torso. New skin was transplanted onto the operated parts of the body. But, unfortunately, after some time the growths appeared again.

5. Heavy combined immunodeficiency. In carriers of this disease, the immune system is inactive. People started talking about the disease after the film “The Boy in the Plastic Bubble,” which appeared on screens in 1976. It tells the story of a small disabled boy, David Vetter, who is forced to live in a plastic bubble. Since any contact with outside world could be fatal for the baby. In the film, everything ends with a touching and beautiful happy ending. The real David Veter died at the age of 13 after doctors failed to strengthen his immune system.

6. Loesch-Nychen syndrome – increased synthesis uric acid. With this disease, too much uric acid enters the blood. This leads to the appearance of kidney stones and bladder, as well as to gouty arthritis. In addition, human behavior also changes. He has involuntary hand cramps. Patients often chew their fingers and lips until they bleed and hit their heads on hard objects. The disease occurs only in male infants.

7. Ectrodactyly. One of birth defects development in which the fingers and/or feet are completely absent or underdeveloped. Caused by a malfunction of the seventh chromosome. Often a companion to the disease is complete absence hearing

8. Proteus syndrome causes rapid and disproportionate bone growth and skin, caused by a mutation in the AKT1 gene. This gene is responsible for correct height cells. Due to a malfunction in its functioning, some cells rapidly grow and divide, while others continue to grow at a normal pace. This leads to abnormal appearance. The disease does not appear immediately after birth, but only by six months of age.

9. Trimethylaminuria. It is one of the rarest genetic diseases. There are not even statistics on its distribution. In those suffering from this disease, trimethylamine accumulates in the body. This is a substance with a sharp unpleasant smell, reminiscent of the smell of rotten fish and eggs, is released along with sweat and creates an unpleasant fetid amber around the patient. Naturally, people with such a genetic malfunction avoid crowded places and are prone to depression.

10. Marfan syndrome. Occurs in one in twenty thousand people. This disease disrupts the development connective tissue. Carriers of this gene defect have disproportionately long limbs and hypermobile joints. Patients also experience visual system disorders and spinal curvature.

Vestigial structures and compromise structures can still be found in the human body, which are very definite evidence that our species has a long evolutionary history, and that it did not just appear out of nowhere.

This article contains some examples of beneficial mutations...

Apolipoprotein AI-Milano

Heart disease is one of the scourges of industrialized countries. It's a legacy we inherit from our evolutionary past, when we were programmed to crave energy-rich fats, then a rare and valuable source of calories but now a cause of clogged arteries. However, there is evidence that evolution has potential that is worth exploring.

All people have a gene for a protein called apolipoprotein AI, which is part of the system that transports cholesterol through the bloodstream. Apo-AI is one of the high-density lipoproteins (HDL) that is already known to be beneficial because it removes cholesterol from artery walls. A mutated version of this protein is known to exist among a small community of people in Italy, called apolipoprotein AI-Milano, or Apo-AIM for short. Apo-AIM works even more effectively than Apo-AI at removing cholesterol from cells and dissolving arterial plaque, and additionally acting as an antioxidant to prevent some of the damage from inflammation that typically occurs with arteriosclerosis. Compared to other people, people with the Apo-AIM gene have a significantly lower risk of heart attack and stroke, and pharmaceutical companies are now planning to bring a man-made version of the protein to market as a cardioprotective drug.

Other drugs are also being produced based on another mutation in the PCSK9 gene that produces a similar effect. People with this mutation have an 88% reduced risk of developing heart disease.

Increased bone density

This mutation was discovered by chance when a young man and his family from the Midwest were in a serious car accident and walked away from the scene without a single broken bone. X-rays revealed that they, like other members of this family, had much stronger and denser bones than is usually the case. The doctor involved in the case reported that "none of these people, whose ages ranged from 3 to 93 years, ever broke a bone." In fact, they have proven to be not only immune to injury, but also to normal age-related skeletal degeneration. Some of them had a benign bony growth on the roof of their mouth, but other than that the disease had no other side effects - other than, as the article dryly noted, it made swimming difficult. As with Apo-AIM, some pharmaceutical firms are exploring the possibility of using it as a starting point for therapies that could help people with osteoporosis and other skeletal diseases.

Malaria resistance

In 2001, Italian researchers studying the population of the African country of Burkina Faso discovered a protective effect associated with a different variant of hemoglobin called HbC. People with just one copy of this gene have a 29% lower risk of contracting malaria, while people with two copies can enjoy a 93% reduction in risk. In addition, this gene variant causes, at worst, mild anemia, and not at all debilitating sickle cell disease.

Tetrochromatic vision

The gene for one type of retinal cone, mainly responsible for the blue tint, was found on the Y chromosome. Both other types, sensitive to red and green, are found on the X chromosome. Because males have only one X chromosome, a mutation that damages the gene responsible for red or green hues will result in red-green color blindness, while females will retain a backup copy. This explains the fact why this disease is almost exclusively confined to men.

But the question arises: what happens if a mutation in the gene responsible for the color red or green does not damage it, but shifts the color range for which it is responsible? The genes responsible for red and green colors appeared exactly like this, as a consequence of duplication and divergence of a single hereditary retinal cone gene.

We also have evidence that in rare cases this has already happened. During a color discrimination study, at least one woman performed exactly as one would expect from a true tetrachromat.

We're already about We discussed Concetta Antico with you– an artist from San Diego, she is a tetrachromat.

Less need for sleep

Not everyone needs eight hours of sleep: scientists from the University of Pennsylvania have discovered a mutation in the little-studied gene BHLHE41, which, in their opinion, allows a person to fully rest in a shorter amount of sleep. In the study, researchers asked a pair of non-identical twins, one of whom had the aforementioned mutation, to abstain from sleep for 38 hours. The “mutant twin” slept only five hours in everyday life - an hour less than his brother. And after deprivation, he made 40% fewer errors in tests and it took him less time to fully restore cognitive function.

Hyperelastic skin

Ehlers-Danlos syndrome is a genetic connective tissue disease that affects joints and skin. Despite a number of serious complications, people with this disease are able to painlessly bend their limbs at any angle. The character of the Joker in Christopher Nolan's The Dark Knight is partly based on this syndrome.

Echolocation

Eternal youth

It sounds much better than it actually is. A mysterious illness dubbed "Syndrome X" prevents a person from ever showing signs of growing up. A famous example is Brooke Megan Greenberg, who lived to be 20 years old and at the same time physically and mentally remained at the level of a two-year-old child. Only three cases of this disease are known.

Insensitivity to pain

Superpower

One of the most popular abilities among superheroes, but one of the rarest in the real world. Mutations associated with a lack of the protein myostatin lead to a significant increase in human muscle mass with a lack of growth of adipose tissue. There are only two known cases of such defects among all people, and in one of them a two-year-old child has the body and strength of a bodybuilder.

Golden Blood

Scientists have been racking their brains for centuries about how to create one single universal group, people with whom there will be a minimum risk for various diseases and deficiencies. Therefore, today it has become possible to “zero” any blood group. This will significantly reduce the risk of various complications and diseases in the near future. Thus, studies have shown that both men and women have the lowest risk of developing CHD. Similar observations have been carried out for more than 20 years. These people answered specific questions about their health and lifestyle over a period of time.

All existing data was published on various sources. All studies have led to the fact that people with the zero group actually get sick less and have the lowest likelihood of developing coronary artery disease. It is also worth noting that the Rh factor does not have any specific effect. Therefore, the zero blood group does not have any Rh factor, which can separate one or another group. One of the most important reasons turned out to be that each blood also has different coagulability. This further complicates the situation and misleads scientists. If you mix the zero group with any other and do not take into account the level of coagulation, this can lead to the development of atherosclerosis and death in a person. At the moment, the technology of converting one blood group into zero is not so widespread that every hospital can use it. Therefore, only those common medical centers that operate at a high level are taken into account. The zero group is a new achievement and discovery of medical scientists, which today is not even familiar to everyone.

Humanity is faced with a huge amount questions, many of which still remain unanswered. And those closest to a person are related to his physiology. A persistent change in the hereditary properties of an organism under the influence of external and internal environment– mutation. This factor is also an important part natural selection, because this is a source of natural variability.

Quite often, breeders resort to mutating organisms. Science divides mutations into several types: genomic, chromosomal and genetic.

Genetic is the most common, and it is the one we encounter most often. It consists in changing the primary structure, and therefore the amino acids read from the mRNA. The latter are arranged complementary to one of the DNA chains (protein biosynthesis: transcription and translation).

The name of the mutation initially had any abrupt changes. But modern ideas information about this phenomenon emerged only in the 20th century. The term “mutation” itself was introduced in 1901 by Hugo De Vries, a Dutch botanist and geneticist, a scientist whose knowledge and observations revealed Mendel’s laws. It was he who formulated modern concept mutations, and also developed mutation theory, but around the same period it was formulated by our compatriot Sergei Korzhinsky in 1899.

The problem of mutations in modern genetics

But modern scientists have made clarifications regarding each point of the theory.
As it turns out, there are special changes that accumulate over the course of generations. It also became known that there are face mutations, which consist in a slight distortion of the original product. Regulations on re-emergence new biological characteristics concerns exclusively gene mutations.

It is important to understand that determining how harmful or beneficial it is depends largely on the genotypic environment. Many factors external environment capable of disrupting the ordering of genes, the strictly established process of their self-reproduction.

In the process of natural selection, man acquired not only useful features, but also not the most favorable ones related to diseases. AND human species pays for what it receives from nature through the accumulation of pathological signs.

Causes of gene mutations

Mutagenic factors. Most mutations have a detrimental effect on the body, disrupting traits regulated by natural selection. Every organism is predisposed to mutation, but under the influence of mutagenic factors their number increases sharply. These factors include: ionizing, ultraviolet radiation, elevated temperature, many connections chemical substances, as well as viruses.

Antimutagenic factors, that is, factors protecting the hereditary apparatus, can safely be attributed to degeneracy genetic code, removal of unnecessary sections that do not carry genetic information (introns), as well as the double strand of the DNA molecule.

Classification of mutations

1. Duplication. In this case, copying occurs from one nucleotide in the chain to a fragment of the DNA chain and the genes themselves.
2. Deletion. In this case, part of the genetic material is lost.
3. Inversion. With this change, a certain area rotates 180 degrees.
4. Insertion. Insertion from a single nucleotide to parts of DNA and a gene is observed.

IN modern world we are increasingly faced with the manifestation of change various signs both in animals and in humans. Mutations often excite seasoned scientists.

Examples of gene mutations in humans

1. Progeria. Progeria is considered to be one of the rarest genetic defects. This mutation appears in premature aging body. Most patients die before reaching the age of thirteen, and a few manage to save life until the age of twenty. This disease develops strokes and heart disease, and that is why, most often, the cause of death is heart attack or stroke.
2. Yuner Tan Syndrome (YUT). This syndrome is specific in that those affected move on all fours. Typically, SUT people use the simplest, most primitive speech and suffer from congenital brain failure.
3. Hypertrichosis. It is also called “werewolf syndrome” or “Abrams syndrome”. This phenomenon traced and documented since the Middle Ages. People susceptible to hypertrichosis are characterized by an amount exceeding the norm, especially on the face, ears and shoulders.
4. Severe combined immunodeficiency. Susceptible this disease already at birth are deprived of effective immune system which the average person has. David Vetter, thanks to whom in 1976 this disease gained fame, died at the age of thirteen, after an unsuccessful attempt surgical intervention in order to strengthen the immune system.
5. Marfan syndrome. The disease occurs quite often and is accompanied by disproportionate development of the limbs and excessive mobility of the joints. Much less common is a deviation expressed by fusion of the ribs, which results in either bulging or sinking of the chest. A common problem susceptible to bottom syndrome is curvature of the spine.

Incredible facts

Compared to many other species, all humans have very similar genomes

However, even minor changes in our genes or environment can contribute to the development of traits in a person that will make him unique.

These differences may manifest themselves in ordinary ways, such as hair color, height, or facial structure, but sometimes a person or certain group people develop something that clearly distinguishes him/them from the rest.

Genetic mutations

10. People who are not genetically predisposed to an “overdose” of cholesterol

While most of us have to worry about how much we consume fried food, and everything that is included in the list of foods that increase cholesterol levels, Few people can eat everything and not worry about it.

In fact, no matter what such people eat, their " bad cholesterol" (the amount of low-density lipoprotein in the blood, which is associated with heart disease) is virtually non-existent.

These people were born with a genetic mutation. Specifically, they are missing a working copy of a gene known as PCSK9, and although it is considered bad luck to be born with a missing gene, in this case Apparently there are some positive side effects.

After scientists discovered a link between the absence of this gene and cholesterol about 10 years ago, pharmaceutical companies began actively working on creating a pill that could block the operation of PCSK9 in an ordinary person.

Work on creation this drug almost completed. In early studies, patients receiving it experienced a 75 percent reduction in cholesterol levels. So far, scientists have been able to detect this congenital mutation in several African-Americans, their risk of developing cardiovascular diseases 90 percent lower compared to an ordinary person.

Disease resistance

9. HIV resistance

Many things can destroy humanity: an asteroid, a nuclear explosion, or extreme climate change. But the most terrible threat is several types of super-virulent viruses. If disease attacks humanity, then Only those few whose immunity has super-strength will have a chance to survive.

Fortunately, we know that there are indeed people who are resistant to certain diseases. Let's take HIV, for example. Some people have a genetic mutation that disables the CCR5 protein.

The HIV virus uses this protein as a doorway into human cells. If this protein does not work in a person, then HIV cannot penetrate cells, and The likelihood of becoming infected with this virus is extremely low.

Scientists say people with this mutation are resistant to the virus rather than immune to it, as several people without this protein have even died from AIDS. Apparently some unusual species HIV has figured out how to use other CCR5 proteins to enter cells. HIV is very inventive, which is why it is so scary.

People with two copies of the defective gene are most resistant to HIV. Currently, this mutation is present in 1 percent of people of Caucasian ethnicity, and it is even less common to find it in representatives of other ethnic groups.

8. Resistance to malaria

Those who are highly resistant to the development of malaria are carriers of another fatal disease: sickle cell anemia. Of course, no one wants to be protected from malaria, but at the same time, die from blood cell disease.

However, there is one situation where having the sickle cell gene pays off. To understand how this works, we must learn the basics of both diseases.

Sickle cell disease causes changes in the shape and composition of red blood cells, making it difficult for them to pass through the bloodstream, causing they don't get enough oxygen.

But you can be immune to malaria without becoming anemic. For sickle cell malaria to develop, a person must inherit two copies of the mutant gene, one from each parent.

If a person is a carrier of only one, then he has enough hemoglobin to resist malaria, at the same time He will never develop full-blown anemia.

Because of its ability to fight malaria, this mutation is highly geographically selective, and is distributed mainly in those regions of the world where malaria is known firsthand. In such areas, 10-40 percent of people are carriers of the mutation gene.

Gene mutations

7. Cold resistance

Eskimos and other groups of people who live in extremely cold weather conditions, have adapted to this way of life. Have these people simply learned to survive, or are they biologically wired differently?

Residents of cold conditions have excellent physiological reactions on low temperatures compared to those living in milder conditions.

And apparently, genetic components are also involved in these reactions, because even if a person moves to a colder environment and lives there for several decades, his body will still will never reach that level of adaptation with whom the locals live.

For example, researchers have found that native Siberians are much better adapted to cold conditions compared to Russians living in the same community but not born in those conditions.

For people for whom cold climates are native, higher basal metabolic rate (about 50 percent higher), compared to those accustomed to a temperate climate. In addition, they are able to maintain body temperature well; they have less sweat glands on the body and more on the face.

In one study, experts tested people of different races to compare how their skin temperature changed when exposed to cold. It turned out that Eskimos are able to hold maximum high temperature bodies.

These types of adaptations may partly explain why Indigenous Australians can sleep on the ground during cold nights (without special clothing or shelter) without getting sick, and also why Eskimos can live most their lives at sub-zero temperatures.

The human body perceives heat much better than cold, so it is surprising that people manage to live in the cold, not to mention feel great about it.

6. Good adaptation to high latitudes

Most climbers who have summited Everest would not have done so without one of the local Sherpa guides. Surprisingly, Sherpas often go ahead of adventurers in order to install ropes and ladders so that other climbers have the opportunity to conquer the rocks.

There is no doubt that the Tibetans and Nepalese are physically more adapted to life in such conditions, but what exactly allows them to work actively in oxygen-free conditions, while a common person must fight to survive?

Tibetans live at altitudes of over 4,000 meters and are accustomed to breathing air that contains 40 percent less oxygen, than air under normal conditions.

Over the centuries, their bodies adapted to this environment, so they developed large chests and great power of the lungs, which allows them to let more air into the body with each breath.

Unlike plains dwellers, whose bodies produce more red blood cells when exposed to reduced content oxygen in the air, "high altitude people" have evolved to do the exact opposite: their bodies produce fewer blood cells.

This is because the increase in the number of red blood cells in conditions of low oxygen levels during short period time will help a person get more life-saving air. However, over time, the blood thickens, which can lead to the formation of blood clots and other deadly complications.

Besides, Sherpas have better blood flow to the brain and are generally more susceptible to altitude sickness.

Even if Tibetans move to live at lower altitudes, they retain these characteristics. Experts have found that many of these features are not just phenotypic deviations (that is, disappearing at low altitudes), but full-fledged genetic adaptations.

One specific genetic change occurred in a piece of DNA known as EPAS1, which encodes a regulatory protein. This protein detects oxygen and controls the production of red blood cells. This explains why Tibetans do not produce more red blood cells when deprived sufficient quantity oxygen.

The Han Chinese, the lowland relatives of the Tibetans, do not share these genetic characteristics with them. The two groups separated from each other approximately 3,000 years ago. This suggests that the adaptations evolved over about 100 generations (a relatively short time in evolutionary terms).

Rare genetic mutations

5. Immunity to brain diseases

In case you needed another reason to stop eating your own kind, here it is: cannibalism is not the healthiest choice. An analysis of the Fore people of Papua New Guinea in the mid-20th century showed us that they were experiencing an epidemic kuru – degenerative and fatal disease brain, common in those who eat other people.

Kuru is a prion disease associated with Creutzfeldt-Jakob disease in humans and spongiform encephalopathy (mad cow disease) in cattle. cattle. Like all prion diseases, Kuru empties the brain, filling it with spongy holes.

U infected person Memory and intellect deteriorate, he begins to suffer from convulsions, and his personality itself degrades. Sometimes people can live with prion disease for many years, but in the case of kuru, sufferers usually die within a year.

It is important to note that, although very rare, a person can still inherit prion disease. However, it is most often transmitted through eating contaminated human or animal meat.

Initially, anthropologists and doctors did not know why kuru had spread throughout the Fore tribe. In the late 1950s, everything finally fell into place. Infection has been found to be transmitted during absorption "funeral cake" - eating a deceased relative as a sign of respect.

Women and small children mostly took part in the cannibalistic ritual. Consequently, they were the main victims. Shortly before this burial practice was banned, in some Fore villages There are practically no young girls left.

Brain tissue of an infected person, white holes - particles eaten by the disease

However, not everyone who had kuru died from it. The survivors were found changes in a gene called G127V, which gave them immunity to brain disease. Today the gene is widespread among the Fore people, as well as among the tribes living in the immediate vicinity.

This is surprising because kuru appeared in the region around 1900. This incident is one of the strongest and most recent examples of natural selection in humans.

The rarest blood

4. Golden Blood

Although we have often been told that blood type O is a universal blood type that suits everyone, this is not the case. In fact, the whole system is more complex mechanism than many of us believe.

Although most are aware of the existence of only eight blood types (A, B, AB and O, each of which can be Rh positive or Rh negative), there are currently 35 known systems blood groups, with millions of variations in each system.

Blood that does not enter the ABO system is extremely rare, and it is very difficult for a person with such a group to find a donor if he suddenly needs a transfusion.

By far the most unusual blood is "Rh - zero". As the name suggests, it does not contain any antigens in the Rh system. This is not the same as the absence of the Rh factor, because the blood of people who do not have the Rh D antigen is called “negative” (A-, B-, AB-, O-).

There is absolutely no Rh antigen in this blood. This is such unusual blood that on our planet There are a little more than 40 people whose blood is “Rh-zero”.