Beautiful human mutations. The most terrible genetic mutations (Photo)
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 a certain group of people develop something that clearly distinguishes him/her from others.
Genetic mutations
10. People who are not genetically predisposed to an “overdose” of cholesterol
While most of us have to worry about the amount of fried food we consume and what is on the list of cholesterol-raising foods, Few people can eat everything and not worry about it.
In fact, no matter what these 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 while it is considered bad luck to be born with the missing gene, in this case there appears to be some positive side effects.
After scientists discovered a link between the absence of this gene and cholesterol about 10 years ago, pharmaceutical companies began to actively work 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 door to enter 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. Some unusual types of HIV appear to have figured out how to use other CCR5 proteins to get into 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 environments have different physiological responses to low temperatures compared to those living in milder environments.
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 of 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 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 ordinary 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 powerful lungs, allowing them to take in more air 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"evolved to do the exact opposite: their bodies produce fewer blood cells.
This is because increasing the number of red blood cells in low oxygen conditions for a short period of time will help a person get more life-saving air. However, over time, the blood thickens, which can lead to the formation 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 particular genetic change occurred in a section of DNA known as EPAS1, which codes for 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 of sufficient oxygen.
The Han Chinese, the lowland relatives of the Tibetans, do not share these genetic characteristics. The two groups separated from each other approximately 3,000 years ago. This suggests that adaptations evolved over about 100 generations (relative to short time from an evolutionary point of view).
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 most healthy 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 a large 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 deteriorates. 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 people 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”.
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 industrialized countries. We inherit it 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 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.
Others are also produced medicines, 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, 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 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 various shades colors. 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.
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. 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. 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 red or green color does not damage it, but moves it color scheme for which he 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 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. "Twin Mutant" and everyday life slept only five hours - 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, necessary for full recovery 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 up from eyes closed in the center of the room and loudly clicking his tongue at 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. Mysterious disease, which has been dubbed “Syndrome X,” prevents a person from showing any 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 same level. 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 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 that work on high level. 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. Also this factor- an important part of natural selection, because it is the 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 complementarily 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 the modern concept of mutation, and also developed the 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. The provision on the re-emergence of 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 chemicals, as well as viruses.
Antimutagenic factors, that is, factors protecting the hereditary apparatus, can safely be attributed to the degeneracy of the genetic code, the 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 of one nucleotide to parts of DNA and a gene is observed.
IN modern world We are increasingly faced with the manifestation of changes in various signs in both animals and humans. Mutations often excite seasoned scientists.
Examples of gene mutations in humans
1. Progeria. Progeria is considered 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 susceptible to it 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 has been 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, they are deprived of the effective immune system that 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.
There are a lot of phenomena in the world that are quite difficult to explain. Why and how do such things happen? It's not entirely clear, but scientists are exploring this area. We present to your attention 10 genetic mutations found in people.
Classmates
Most often, children who are sick with progeria do not live to see the age of 13; of course, there are exceptions and the child celebrates his twentieth birthday, but such cases are rare. Most often, children with this type of mutation die from heart attacks or strokes. Moreover, for every 8 million children, one child is born with progeria. The disease is caused by a mutation in a person's lamin A/C gene, a protein that provides support to cell nuclei.
Progeria includes associated symptoms: hard skin no hair, slow growth, abnormal bone development, characteristic nose shape. The interest of gerontologists in this mutation continues unabated; today they are trying to understand the relationship between the presence of a defective gene and the processes leading to the aging of the body.
JTS or Youner Tang Syndrome, the main symptom of this human mutation is walking on 4 limbs. This mutation was discovered by biologist Yuner Tan while studying the inhabitants of Turkey, the rural Ulas family, consisting of 5 people. A person with this anomaly cannot speak coherently, which is due to congenital brain deficiency. A biologist from Turkey studied this type of human mutation and described it in the following words: “The basis of genetic mutation is the return of human development to the reverse stage of human evolution.
The mutation is caused genetic abnormality, that is, a deviation in the gene contributed to the relapse of walking on hands and feet at the same time (quadropedalism), from walking upright on two legs (bipedalism). In his research, Tang identified the punctuated equilibrium mutation. In addition, this deviation, according to the biologist, can be used as a living model of the evolutionary changes that humans have undergone as a species from its appearance to the present. Some do not accept this theory; in their opinion, the appearance of people with Yuner Tang Syndrome develops regardless of the genome.
Abrams syndrome or hypertrichosis affects 1 in a billion people on the planet. Scientists know of only fifty recorded cases of this mutation since the Middle Ages. A person who has a mutated gene has an increased a large number body hair. This mutation is caused by a disruption of the important connection between the epidermis and dermis back in intrauterine development hair follicle. During this mutation in a three-month-old fetus, signals coming from the dermis seem to notify the follicle of its future shape.
And the follicle, in turn, signals to the skin that the follicle is formed. As a result, the hairs grow evenly, that is, they are located at the same distance. When one of the genes responsible for this delicate connection is mutated during the formation hairline, hair follicle cannot inform the dermis about the number of already formed bulbs, so the bulbs seem to be stuck on top of each other, forming dense “fur” on human skin.
A rather rare type of mutation that does not allow one to acquire immunity resistant to the human papillomavirus is called epidermodysplasia verruciformis. This mutation does not prevent papules or scaly patches from appearing on the skin of the legs, arms, and face. The “growth” from the outside looks like warts, but sometimes they resemble tree bark or horny substance. In fact, these formations are a tumor, most often appearing in people who have this gene deviation for 20 years, in areas of the skin that are exposed to open sunlight.
A method capable of completely eliminating this disease has not been invented, but using modern surgical methods You can slightly reduce its manifestation and slightly slow down the growth of tumor growths. Information about Epidermodysplasia verruciformis became available in 2007, with the appearance of a documentary film on the Internet starring the Indonesian Dede Koswara. In 2008, when he was 35 years old at that time, he suffered complex operation, in which he had 6 kg of growths removed from different parts of his body, such as his arms, head, torso and legs.
Doctors transplanted new skin to the areas from which the growths were removed. Thanks to this operation, Kosvaro got rid of a total of 95% of warts. But after a while, the warts began to appear again, and therefore doctors recommended surgery every two years. Indeed, in the case of Kosvaro, this is vitally important; after removing the growths, he can eat, hold a spoon and get dressed on his own.
The mutation of the human gene led to a situation where people began to be born without any immune system capable of coping with viruses. Severe combined immunodeficiency became known to the general public thanks to the movie “The Boy in the Plastic Bubble.” The film is based on the story of the difficult life of two boys born with disabilities, Ted DeVita and David Vetter. Movie hero little boy, who was forced to exist in a special cabin that isolated him from open space, because the effects of microbes contained in unfiltered air could be fatal for the boy.
The prototype of the movie hero Witter lived to the age of thirteen; his death occurred after a failed attempt to transplant his bone marrow. This immune abnormality results from changes in several genes. These changes negatively affect lymph production. Scientists believe that the mutation occurs due to a lack of adenosine deaminase. Some methods have become available to doctors to treat TCI; gene therapy is suitable for this.
This mutation affects one newborn boy out of 380 thousand. With this mutation, the production of uric acid increases, which appears as a result of natural metabolic processes. Men affected by SLN have comorbidities such as gout and kidney stones. This occurs due to the fact that a large amount of uric acid enters the blood.
This mutation is responsible for changes in behavior, as well as in the neurological functions of a man. Patients often experience sharp spasms of the muscles of the limbs, which can manifest themselves as convulsions or erratic swinging of the limbs. During such attacks, patients often injure themselves. As you know, doctors have learned to treat gout.
This mutation is visible from the outside; a person has no phalanges of the fingers at all, in some cases they are underdeveloped. The patient's arms and legs resemble a claw to some people. This type mutations are almost impossible to encounter. Sometimes children are born with all their fingers, but they are fused. Currently, doctors separate them by performing simple plastic surgery. But a larger percentage of children with this deviation have fingers that are not fully formed. Sometimes ectrodactyly causes deafness. Scientists call the source of the disease a disorder in the genome, namely deletion, translocation of the seventh chromosome and inversion.
A striking representative of this mutation is the Elephant Man or, in his days, Joseph Merrick. This mutation is caused by neurofibromatosis type I. Bone tissue, together with the skin, increase at an abnormally rapid pace, while violating the natural proportions. The first symptoms of Proteus syndrome in a child appear no earlier than six months of age. It proceeds individually. Typically, 1 in a million people suffer from Proteus syndrome. Scientists know only a few hundred facts about this disease.
This human mutation is a consequence of changes in the AKT1 gene, which is responsible for cell division. In this disease, a cell that has abnormalities in its structure grows and divides at a tremendous uncontrolled speed, while a cell without an anomaly grows at the prescribed pace. As a result, the patient has a mixture of normal and abnormal cells. It doesn't always look aesthetically pleasing.
It is a rare mutational disorder, so scientists cannot clearly indicate the number of people affected by it. But a person suffering from trimethylaminuria can be noticed at first glance. The patient accumulates the substance trimethylamine. The substance changes structure skin discharge, in connection with this, sweat smells quite unpleasant, for example, some can smell like rotten fish, urine, rotten eggs.
The female sex is prone to this anomaly. The intensity of the odor appears in full intensity a few days before menstruation, and it is also affected by the intake hormonal medications. Scientists believe that the level of trimethylamine released directly depends on the amount of estrogen and progesterone. People suffering from this syndrome are prone to depression and live isolated lives.
The mutation is quite common; on average, one child in 20 thousand is born with this mutation. This is a disorder associated with abnormal development connective tissue. The most common form today is myopia, as well as disproportionate length of an arm or leg. Sometimes there are cases of abnormal development of joints. People with this mutation can be recognized by their excessively long and thin arms.
Very rarely, a person with this anomaly has ribs fused together, and the bones of the chest seem to sink in or protrude outward. When the disease is advanced, deformation of the spine occurs.
Historically, people with such mutations were labeled as freaks and monsters, but today we know that the unusual appearance- only part wide range genetic variations of our species. We offer you a selection of the ten most unusual mutations found in people.
1. Progeria
Most children with progeria die around the age of 13, but some live into their 20s. Typically, the cause of death is a heart attack or stroke. On average, progeria occurs in only one child in 8,000,000.
The disease is caused by mutations in the lamin A/C gene, a protein that provides support to cell nuclei. Other symptoms of progeria include tough, completely hairless skin, bone abnormalities, slow growth and characteristic shape nose Progeria is of great interest to gerontologists who hope to discover the connection between genetic factors and the aging process.
2. Yuner Tan syndrome
Yuner Tan syndrome (UTS) is characterized primarily by the fact that people suffering from it walk on all fours. It was discovered by Turkish biologist Yuner Tan after studying five members of the Ulas family in rural areas Turkey. Most often, people with SUT use primitive speech and have congenital brain deficiency. In 2006, a film about the Ulas family was filmed documentary called "The Family Walking on All Fours." Tan describes it this way:
“The genetic nature of the syndrome suggests a reverse step in human evolution, most likely caused by a genetic mutation, the reverse process of transition from quadropedalism (walking on four limbs) to bipedalism (walking on two). In this case, the syndrome corresponds to the theory of punctuated equilibrium.
The new syndrome, according to Tan, can be used as a living model of human evolution. Some researchers, however, do not take this seriously and believe that the manifestation of SUT does not depend on the genome.
3. Hypertrichosis
Hypertrichosis is also called "werewolf syndrome" or "Abrams syndrome". It affects only one person in a billion, and only 50 cases have been documented since the Middle Ages. People suffering from hypertrichosis have an excessive amount of hair on the face, ears and shoulders. This occurs due to disruption of the connections between the epidermis and dermis during the formation of a three-month fetus. hair follicles. As a rule, signals from the developing dermis “tell” the follicles their shape. The follicles, in turn, also signal to the skin layers that there is already one follicle in this area, and this leads to hairs growing on the body at approximately the same distance from each other. In the case of hypertrichosis, these connections are disrupted, which leads to the formation of too dense hair in those areas of the body where it should not be.
4. Epidermodysplasia verruciformis
Epidermodysplasia verruciformis is an extremely rare disorder that makes its carriers prone to the widespread human papillomavirus (HPV). This infection causes scaly patches and papules to form on the skin ( squamous cell carcinoma skin) growing on the arms, legs and even the face. These "growths" look like warts or more often resemble horn or wood. Typically, skin tumors begin to appear in people between the ages of 20 and 40 in areas exposed to sunlight. Methods complete healing does not exist, however with the help intensive care you can reduce or temporarily stop the spread of growths.
The public learned about this genetic disease in 2007, when a video of 34-year-old Indonesian Dede Kosvara appeared on the Internet. In 2008, a man underwent surgery to remove six kg of growths from his body. Horny growths were removed from the arms, head, torso and legs, and new skin was transplanted into these areas. In total, Kosvar was able to get rid of 95% of warts. Unfortunately, after some time they began to grow again, and doctors believe that the operation will have to be repeated every two years so that Kosvara can at least hold a spoon.
5. Severe combined immunodeficiency
People with this genetic disorder are born without an effective immune system. The disease became known after the 1976 film The Boy in the Plastic Bubble, inspired by the lives of two disabled boys, David Vetter and Ted DeVita. The main character, a little boy, is forced to live in a plastic cabin isolated from the outside world, since unfiltered air and exposure to microorganisms can be fatal to him. The real Vetter was able to live in this way until he was 13 years old, but died in 1984 after a failed transplant bone marrow- medical attempts to strengthen the immune system.
The disorder is caused by a number of genes, including those that cause defects in T and B cell responses, which ultimately have a negative impact on the production of lymphocytes. It is also believed that this disease occurs due to the absence of adenosine deaminase. Several treatment methods using gene therapy are now known.
6. Loesch-Nychen syndrome
SLN affects one in 380,000 male infants and results in increased uric acid synthesis. Uric acid is released into the blood and urine as a result of events occurring in the body chemical processes. In people with SLI, too much uric acid enters the bloodstream, which accumulates under the skin and eventually causes gouty arthritis. It can also lead to the formation of kidney and bladder stones.
The disease also affects neurological function and behavior. Those suffering from SLI often experience involuntary muscle contractions, resulting in spasms and/or erratic limb flailing. It happens that patients mutilate themselves: they hit their heads on hard objects, bite their fingers and lips. Allopurinol may help with gout, but there are no treatments for the neurological and behavioral aspects of the disease.
7. Ectrodactyly
People with ectrodactyly have either missing or underdeveloped fingers or toes, causing their hands or feet to resemble claws. Fortunately, such genomic abnormalities are rare. Ectrodactyly can manifest itself in different ways, sometimes the fingers simply grow together, in which case they can be separated using plastic surgery, in other cases, the fingers are not even fully formed. The disease is often accompanied by complete hearing loss. The causes of the disease are genomic disorders, including deletions, translocations and inversions in the seventh chromosome.
8. Proteus syndrome
Joseph Merrick, known as the Elephant Man, probably suffered from this disease. Proteus syndrome is caused by neurofibromatosis type I. In Proteus syndrome, bones and skin the patient may begin to increase abnormally quickly, as a result of which the natural proportions of the body are disrupted. Signs of the disease usually do not appear until 6–18 months after birth. The severity of the disease depends on the individual. On average, one person in a million suffers from Proteus syndrome. Only a few hundred such cases have been documented throughout history.
The disorder is the result of a mutation in the AKT1 gene, which is responsible for regulating cell growth, causing some mutated cells to grow and divide at an unimaginable rate, while other cells continue to grow at a normal pace. The result is a mixture of normal and abnormal cells, causing external abnormalities.
9. Trimethylaminuria
This genetic disorder is so rare that the incidence rate is not even known. But if someone next to you suffers from this, you will immediately notice. The fact is that trimethylamine accumulates in the patient’s body, which, when released along with sweat, creates bad smell- the person smells like rotten fish, rotten eggs, garbage or urine. Women are generally more susceptible to the disease than men. The intensity of the odor reaches its peak immediately before and during menstruation, or after ingestion. oral contraceptives. Apparently, this is due to female sex hormones like progesterone and estrogen.
Of course, as a result, patients are often depressed and prefer to live in isolation.
10. Marfan syndrome
Marfan syndrome is not a rare disease; as a rule, it occurs in one person in 20,000. It is a disorder in the development of connective tissues. One of the most common forms of deviation is myopia, but even more often the disease manifests itself in disproportionate growth of bones in the arms and legs and excessive mobility of the knees and elbow joints. People with Marfan syndrome tend to have long and thin arms and legs. Less commonly, patients’ ribs may fuse together, resulting in the chest either protruding outward or, conversely, sinking. Another problem is spinal curvature.
