Genetics are passed on through generations. View full version
In which case, you might be concerned about the question: after how many generations are twins born, and who can have twins? Let's say you have twins. Where? After all, no one remembers about the cases of twins in your relatives. Then the question of who can have twins will become relevant for you. And for your children it will be interesting question: after how many generations are twins born, i.e. It’s like they may or may not have two babies at once. What about your grandchildren, your children’s children? Here we will tell you who can have twins using specific examples, and show how many generations it takes for twins to be born.
We talked quite a lot about the probability of having twins, how it turns out and what needs to be done for it to be born. We even wrote a separate article on how twins are inherited, through which line twins are transmitted or a story: how twins are inherited. In it we described in detail who can have twins. We also promised to give specific examples. It's time to do it.
We here by default believe that the possibility of giving birth to twins manifests itself immediately. Then who can have twins? Those who had it in their family. That is, if the appearance of twins is possible, then it will be. But this perfect option. He doesn't exist in life. In most specific cases, even those who have many relatives with multiple pregnancies are less likely to have twins than to have one child at a time.
You need to understand that twins are born only in about 1% of all births. Therefore, anyone who can have twins is very lucky. The maximum percentage on planet Earth is 10%, and that is in the “capital of the twins”, Cándido Godoy, Brazil.
Who can have twins?
Twins can occur in those who have twins or twins in their family. For nature, this is basically the same thing. Only the super- or hyperovulation gene, which is responsible for the maturation of two or more eggs, can be transmitted in a generation. The gene manifests itself in the form of the birth of twins or twins.
How many generations do it take for twins to be born when passed from woman to woman?
The transfer of the gene from woman to woman occurs immediately and with a high probability of its manifestation, i.e. birth of twins.
Who gives birth to twins and twins when transmitted from woman to man
A man's gene does not affect another woman's ability to give birth to twins. And the man himself does not give birth, so manifestations of his gene are possible only if he gives birth to a girl. So she can give birth to twins, but with less opportunity than her grandmother - her father's mother.
As mentioned above, a man’s gene does not help other women give birth to twin children from them. The gene will only appear if a woman has it. So, to find out 
after what generation are twins born when transmitted from man to man, the number of generations must be counted from the last twin in the family to the first girl on the paternal side.
Who can have twins when transmitted from man to woman?
Actually, twins can be born to this woman. After all, it is in her body that the gene can, in principle, manifest itself. In this case, after how many generations are twins born - after one generation, from the first twins on the father's side. In fact, an analogue of the case of transmission of women-man-woman in a sequence of generations.
How many generations do it take for twins to be born?
It seems that from a formal point of view one should reason like this: twins are approximately equal to twins, then 
After how many generations are twins born?
- or immediately after one generation, if the transmission was to a girl
- or through a generation, if it was transmitted through a boy, and he had a girl
- or after two or more generations, when transmitted through a boy-boy
Then who can have twins? Those who had either them or twins. In general, everything is the same as in the case of twins.
However, there is one nuance that is very important for twins and twins.
Twins, they are dizygotic fraternal twins, is indeed inherited due to the transmission of the superovulation gene. For their appearance you need TWO separate eggs ready for fertilization. And twins, they are twins in the everyday sense, they are monozygotic identical twins– do not depend on this gene. This is because in this case ONE egg after fertilization at the stage of early division it is divided into TWO different parts, two future organisms.
Then who can have twins? – in any woman, the superovulation gene has nothing to do with it. Note that the mechanism of formation of monozygotic identical twins is known, but the reasons are not fully understood.
It turns out that after how many generations twins are born is unknown, because monozygotic twins cannot be passed on by inheritance. Their appearance remains a random phenomenon.
After how many generations are twins born - examples
To understand even better how many generations it takes for twins to be born and who can have twins, let’s give a few examples.
After what generation are twins born if you are a woman and had a grandmother with twins?
So, the question is who can have twins if you are a woman. You have a grandmother who once upon a time had twins in her family, but no one remembers anything for sure. It is known for sure that your grandmother had twins (maybe even twins) - boys. In total, my grandmother had three children, the third was a girl.
If you are the offspring of boy twins, then the possibility of you having twins is high. Dad could have given you his superovulation gene from his mother, who is also your grandmother. Moreover, dad himself has never had, and never will have, twins. Then, for anyone who can have twins or twins, the answer is simple - you.
If you are the descendant of a third child - a girl, then there will be two more options for you.
Who can have twins if your mother didn't have twins?
You could still have twins, because... there is heredity. However, your chance of having twins is slim.
Who can have twins if your mother had them?
Here everything is even simpler; you are more likely to have twins. And you don’t have to be a twin sister yourself. That is, you can be a single child, and you also have twin brothers or sisters. And if you are also a twin yourself, then the possibility of having twins is already very high. It is the largest compared to other cases in this example.
After what generation are twins born if you are a woman and had a grandfather with twins?
And again, we pose the question, 
who can have twins if you are a woman. This time you have a grandfather who once upon a time had twins in his family, and again, no one seems to remember anything. It is known for sure that grandfather had twins. Your grandfather had three children in total. The third one is not a twin. The gender of the third child is not particularly important for this example.
- If your mother is a twin, then your chances are the highest.
- Let's assume that your mother is not a twin, then the possibility of having twins is approximately 2 times lower. In any case, whoever can have twins is you, only with varying degrees of possibility.
- Unless your dad is a twin. Then he could pass the gene on to you, and the probability of your birth is also high.
- And if your dad was a twin, then your chance of having twins is even higher and is comparable to the case where your mother is a twin.
After how many generations are twins born - ATTENTION
To finally understand 
After how many generations are twins born in this example, you need to pay attention to the following words. In this example, in ANY case, your grandfather with twins could not influence the birth of his own twins. And since there were twins, then you need to look from the side of his wife - your grandmother. Then we return to the first example, everything there is analogous.
Who can have twins if you are a man?
Everything is simple here, twins or twins can be born along your gene line only to your female descendants. And the further they are in generations from the fact of the birth of twins or twins, the less opportunity they themselves have to give birth to twins.
It turns out that in order to be guaranteed not to have twins, even if your parents had them and you yourself are a twin, you have to be a boy yourself. And it's better for you to have boys. If there are girls, see the examples above.
Genetics is not only an interesting science, but also convenient. Scientific research has proven that much of us does not depend on us, but is inherited. Genes, nothing can be done.
Dominant and recessive
It's no secret that our appearance consists of a number of characteristics that are determined by heredity. You can talk about skin color, hair, eyes, height, build, and so on.
Most genes have two or more variations, called alleles. They can be dominant and recessive.
Complete dominance of one allele is extremely rare, including due to the indirect influence of other genes. Also on appearance The baby is affected by multiple allelism observed in a number of genes.
Therefore, scientists only talk about a higher probability of external signs in children caused by the dominant alleles of their parents, but nothing more.
For example, dark color hair is dominant over light hair. If both parents have black or blond hair, then the child will also be dark-haired.
Exceptions are possible in rare cases if, for example, both parents were blond. If both parents have blond hair, then the likelihood that the baby will be brunette increases. Curly hair with more likely will be inherited because they are dominant. As for eye color, dark colors are also strong: black, brown, dark green.
Such features of appearance as dimples on the cheeks or chin dominate. In a union where at least one partner has dimples, they are most likely to be passed on to the younger generation. Almost all prominent features of appearance are strong. This could be a large, long nose or a hump on it, protruding ears, thick eyebrows, plump lips.
Will the girl be obedient?
Whether a daughter will become a neat girl who loves dolls, or will grow up like a boy playing “Cossack robbers” is largely determined by maternal instinct, which, as it turned out, depends on two genes.
Research conducted by the Human Genom Organization (HUGO) is shocking science community, when they presented evidence that the instinct of motherhood is transmitted exclusively through the male line. That is why scientists say that, according to the behavioral model, girls are more likely to be similar to their paternal grandmothers than to their mothers.
Inherited aggressiveness
Russian scientists in the Human Genome Project were tasked with determining whether aggressiveness, irritability, activity and sociability are genetically inherited traits, or are formed in the process of upbringing. The behavior of twin children aged 7 to 12 months and their genetic connection with the type of parental behavior was studied.
It turned out that the first three traits of temperament are of a hereditary nature, but 90% of sociability is formed in a social environment. For example, if one of the parents is prone to aggression, then with a 94% probability this will happen again in the child.
Alpine genes
Genetics can explain not only external signs, but even national characteristics different nations. Thus, in the Sherpa genome there is an allele of the EPAS1 gene, which increases the presence of hemoglobin in the blood, which explains their adaptability to life in high mountain conditions. No other people have this adaptation, but exactly the same allele was found in the genome of the Denisovans - people who are neither Neanderthals nor species Homo Sapiens. The Denisovans probably interbred with the common ancestors of the Chinese and Sherpas many millennia ago. Subsequently, the Chinese living on the plains lost this allele as unnecessary, but the Sherpas retained it.
Genes, sulfur and sweat
Genes are even responsible for how much a person sweats and how much earwax he has. There are two versions of the ABCC11 gene that are common in the human population. Those of us who have at least one of two copies of the dominant version of the gene produce liquid earwax, while those who have two copies of the recessive version produce solid earwax. Also, the ABCC11 gene is responsible for the production of proteins that remove sweat from the pores in the armpits. People with hard earwax do not produce this kind of sweat, so they do not have problems with odor and the need to constantly use deodorant.
Sleep gene
Dream ordinary person is 7-8 hours a day, however, if there is a mutation in the hDEC2 gene, which regulates the sleep-wake cycle, the need for sleep can be reduced to 4 hours. Carriers of this mutation often achieve more in life and career with the extra time.
Speech gene
The FOXP2 gene plays a role in humans important role in the formation of the speech apparatus. When this became clear, geneticists conducted an experiment to introduce the FOXP2 gene into chimpanzees, in the hope that the monkey would speak. But nothing like this happened - the area responsible for speech functions in humans regulates the vestibular apparatus in chimpanzees. The ability to climb trees during evolution turned out to be much more important for the monkey than the development of verbal communication skills.
Happiness gene
For the past decade, genetics has been struggling to prove that for happy life we need the appropriate genes, or more precisely, the so-called 5-HTTLPR gene, which is responsible for the transport of serotonin (“the hormone of happiness”).
In the last century, this theory would have been considered crazy, but today, when the genes responsible for baldness, longevity or falling in love have already been discovered, nothing seems impossible anymore.
To prove their hypothesis, scientists from the London School of Medicine and School of Economics surveyed several thousand people. As a result, volunteers who had two copies of the happiness gene from both parents turned out to be optimistic people and not prone to any depression. The study results were published by Jan-Emmanuel de Neve in the Journal of Human Genetics. At the same time, the scientist emphasized that other “happy genes” could soon be found.
However, if for some reason you for a long time If you are in a bad mood, you should not rely too much on your body and blame Mother Nature for “depriving you of happiness.” Scientists say that human happiness depends on many factors: “If you are unlucky, you lost your job or broke up with loved ones, then this will be a much stronger source of unhappiness, no matter how many genes you have,” de Neve said .
Genes and diseases
Genes also influence what diseases a person may be prone to. In total, about 3,500 have been described to date, and for half of them the specific culprit gene has been identified, its structure, types of disorders and mutations are known.
Longevity
The longevity gene was discovered by scientists from Harvard Medical School in Massachusetts back in 2001. The longevity gene is actually a sequence of 10 genes that may hold the secret to long life.
During the project, the genes of 137 100-year-old people and their brothers and sisters aged from 91 to 109 years were studied. All subjects were found to have “chromosome 4,” and scientists believe that it contains up to 10 genes that affect health and life expectancy.
These genes, scientists believe, allow their carriers to successfully fight cancer, heart disease and dementia and some other diseases.
Body type
Genes are also responsible for your body type. Thus, a tendency to obesity often occurs in people who have a defect in the FTO gene. This gene disrupts the balance of the “hunger hormone” ghrelin, which leads to impaired appetite and an innate desire to eat more than necessary. Understanding this process gives hope for the creation of a drug that reduces the concentration of ghrelin in the body.
Eye color
It is traditionally believed that eye color is determined by heredity. A mutation in the OCA2 gene is responsible for light eyes. For blue or green color responds to the EYCL1 gene of chromosome 19; for brown - EYCL2; for brown or blue - EYCL3 of chromosome 15. In addition, the genes OCA2, SLC24A4, TYR are associated with eye color.
Back at the end of the 19th century, there was a hypothesis that human ancestors had exclusively dark eyes. Hans Eyberg, a modern Danish scientist at the University of Copenhagen, conducted Scientific research, confirming and developing this idea. According to research results, the OCA2 gene, which is responsible for light shades of eyes, mutations of which disable the standard color, appeared only during the Mesolithic period (10,000-6,000 BC). Hans has been collecting evidence since 1996 and concluded that OCA2 regulates the production of melanin in the body, and any changes in the gene reduce this ability and impair its functioning, causing blue eyes.
The professor also claims that all blue-eyed inhabitants of the Earth have common ancestors, because this gene is inherited. However different shapes alleles of the same gene are always in a state of competition, and the darker color always “wins”, as a result of which parents with blue and brown eyes will have brown-eyed children, and only a blue-eyed couple can have a baby with eyes of cold shades .
Blood type
The blood type of the unborn baby is the most predictable of all hereditary characteristics. Everything is quite simple. Knowing the blood type of the parents, you can tell what type the child will have. So, if both partners have the same blood type, then their baby will have a similar one. With the interaction of 1 and 2, 2 and 2 blood groups, children can inherit one of these two options. Absolutely any blood type is possible in a child whose parents are groups 2 and 3.
Popular computer game Assassin's Creed, which was recently made into a movie, is based on the idea that main character able to “remember” and experience the memories of their long-dead ancestors. In the game and film, a special machine - the Animus - helps the heroes remember the distant past and go through generations.
Although such excursions into the past are now nothing more than science fiction, the idea of genetic memories embedded in our DNA is not so far from the truth.
Transferring the experience of ancestors
In fact, a stunning new study published in the journal Science suggests that experiences that shaped the lives of ancestors can have an impact on the lives of descendants. This connection can remain in the genes for 14 generations.
A team of scientists from the Barcelona Center for Genomic Regulation and the José Carreras Leukemia Research Institute conducted a study on the genes of nematode worms. They concluded that genes are capable of carrying information that potentially reflects the life experiences of distant ancestors.
This discovery captured a unique phenomenon - the longest-lasting form of transmission of genetic information ever discovered in an animal.
What does it mean?
It is still extremely difficult to make similar observations with people, since the life expectancy of people is much longer and the genetic structure is more complex, but the differences in the organization of the genetic material of people and nematode worms are not too radical.
We know that the way our grandparents lived their lives does influence our behavior, but now it's possible that an ancestor who lived centuries ago can still directly influence the way we behave today.
Genetics and genetic memory
Let's digress a little into what exactly genetics does and how we get our DNA from our parents. This is a very specific and comparatively new area biology.
Our genes are inherited from our parents, and their genes are inherited from their parents. If they change or mutate, we inherit those mutations.
However, changes in the genome depend not only on what has been inherited, but also on the environment and life experience. For example, a lifetime in a hot climate will prepare our bodies to cope better with high temperature and the bright sun, and we can pass this information on to our descendants through changes in the genome.
Changes in the environment and life experiences, such as air and water pollution, war, stress and psychological disorders, greatly influence the information carried by genes.
An additional layer of information received from the experience of parents is, as it were, superimposed on top of the DNA chain. Her structure as such does not change, but her “clothing” changes.
Similar transmission of genetic information, derived from the environment and life experiences of ancestors, has already been seen in humans. For example, descendants of Holocaust survivors have significantly reduced levels of cortisol (a stress hormone) in their blood, which means they are more susceptible to negative influence stress, pressure, tension, anxiety and fear.
Conducted research
This particular study focused on Caenorhabditis elegans - tiny nematodes with a very short lifespan. The researchers genetically engineered them by adding a fluorescent protein to their genes, whose behavior they could monitor under ultraviolet light.
The scientists first placed the worms in a cold environment where the gene glowed faintly. By moving the nematodes to a warmer environment, the scientists saw that the gene glowed much more strongly. By returning the study animals to cold room, observers noticed that the gene continued to glow more intensely, as if retaining a “memory” of the warm environment.
Subsequently, not only the fluorescent gene, but also the memory of the warm habitat were passed on to subsequent generations. This means that the descendants of the first nematodes with a fluorescent gene “knew” about a warm environment, without ever experiencing it themselves.
conclusions
Scientists suggest that this form of long-term transmission of genetic experience to descendants is a unique form of biological planning for the future. Worms are very short-lived, so it is likely that ancestors pass on memories of the conditions they experienced to help their descendants prepare for what their environment might be like in the future.
So, if worms can “remember” the experiences of their long-gone ancestors, is the same possible for humans? At the moment it is impossible to get a definite answer to this question, but the possibility exists.
Fantasizing about your capabilities without knowing the limitations is irresponsible. Getting carried away with psychology, forgetting about physiology and genetics, is wrong. The higher grows through the lower, and any psychologist should know the basics of genetics. It is not true that a newborn is just a body with a set of genes: a newborn is already a member of society, it is someone’s child, his mother already loves him and his father is ready to raise him. No one yet knows whether from birth a child has at least the rudiments of reason, will and spirit, but one thing can be said with confidence: from birth a child has his genes, which determine his life and development. Human genetics are the innate characteristics of a person, transmitted through genes.
Genes are sections of DNA that carry information about heredity. Congenital human characteristics transmitted through genes - human genetics. A genotype is a set of genes of an organism, a phenotype is the external manifestations of these genes, a set of characteristics of an organism. A phenotype is everything that can be seen, counted, measured, described simply by looking at a person (blue eyes, blond hair, short stature, choleric temperament, and so on).
In men, the genotype is more variable, in women - the phenotype.
According to some geneticists, genes pass on programs to a greater extent not to the next generation, but through the next generation, that is, your genes will not be in your children, but in your grandchildren. And your children have the genes of your parents.
What do our genes determine? Genes determine our physical and mental characteristics; genes determine that we, as humans, cannot fly and breathe under water, but we can learn human speech and writing. Boys are easier to navigate objective world, girls - in the world of relationships. Some were born with an absolute ear for music, some with an absolute memory, and some with very average abilities.
The child’s abilities also depend on the age of the parents. Brilliant children are most often born in a couple where the mother is 27 years old and the father is 38. However, the healthiest children are born to younger parents, when the mother is between 18 and 27. Your choice? Genes determine many of our character traits and inclinations. Boys have a tendency to work with cars rather than dolls. Genes influence our individual predispositions, including diseases, antisocial behavior, talent, physical or intellectual activity, etc. Is it possible to say that all people from childhood have a natural inclination towards goodness, that man is kind by nature? This is one of the central issues on which debates among psychologists continue.
At the same time, it is important to always remember: inclination pushes a person, but does not determine his behavior. Genes are responsible for inclination, and people are responsible for behavior. And you can work with your inclinations: develop some, make them loved, and leave others outside your attention, extinguish them, forget them...
Genes determine the time when some of our talent or inclination will manifest itself or not.
Genes determine the time when some of our talents can manifest themselves. I came at a good time, when the genes were ready, and it worked a miracle. If you miss the time, you fly past. Today, the child’s sensitivity to developmental processes is high - he “ White list”, “absorbs only the good” and “very talented”, and a year later: “he doesn’t understand anything”, “both in the forehead and in the forehead” and “the apple doesn’t fall far from the tree” (with sadness).
Genes determine when our sex drive awakens and when it falls asleep. Genes influence both happiness and character traits.
After analyzing data from more than 900 pairs of twins, psychologists at the University of Edinburgh found evidence of the existence of genes that determine character traits, a tendency to be happy, and the ability to tolerate stress more easily.
Aggressiveness and goodwill, genius and dementia, autism or extroversion are passed on to children from their parents as inclinations. All this can be changed by education, but in varying degrees, since inclinations also come in different strengths. Whether a child learns or not is also related to his genetics. And let us immediately note: healthy children are quite teachable. Human genetics makes humans an exceptionally learnable creature!
Genes are the carriers of our capabilities, including the ability to change and improve. Interestingly, men and women have different capabilities in this regard. Men are more likely than women to be born with one or another deviation: among men there are more of those who will be very tall and very short, very smart and, conversely, talented and idiots. It seems that nature is experimenting with men... At the same time, if a man was born this way, it is very difficult for him to change this throughout his life. A man is tied to his genotype, his phenotype ( external manifestation genotype) - changes slightly.
If you were born long, you will remain long. A short person can, with the help of sports, rise 1-2 centimeters, but no more.
For women the situation is different. Women are born more identical on average, and there are fewer biological and genetic deviations among them. More often than not, there are fewer average heights, average intelligence, average decency, idiots and crap among women than among men. But also outstanding in intellectual or morally- similar. It seems that evolution, while conducting experiments on men, decides not to take risks on women and invests everything that is most reliable in women. At the same time, individual (phenotypic) variability in women is higher: if a girl was born small relative to others, she will be able to stretch 2-5 cm (more than a guy can)... Women have greater freedom from their genotype, have a greater opportunity than men , change yourself.
Genes give us our capabilities, and genes limit our capabilities.
A proud ear of wheat grows from a grain of wheat, and a beautiful branched apple tree grows from an apple tree seedling. Our essence, our inclinations and the opportunity to realize ourselves are given to us by our genes. On the other hand, only an ear of wheat will grow from a grain of wheat, only an apple tree will grow from an apple tree seedling, and no matter how much a frog inflates, it will not inflate into a bull. She doesn't even have the strength to burst from the strain.
Man is also a part of nature, and all of the above is true for him. Genes determine the limits of our capabilities, including our ability to change ourselves, strive for growth and development. If you were lucky with your genes, you were able to absorb the influences of your parents and teachers, and grew up to be a developed, decent and talented person. Thanks to parents! If you are less fortunate with your genes, and you (suddenly!) were born a down, then in the best environment you will only grow up to be a well-mannered down. In this sense, our genes are our destiny, and we cannot directly change our genes, our abilities to grow and change.
How much is genetically inherent in us is a very controversial question. It is rather true that the more a person moves away from the animal world, the less innate in him and the more acquired. For now, we must admit that most of us have a lot of innate. On average, according to geneticists, genes determine 40% of human behavior.
Genetics can be good or bad, and it also depends on our lifestyle. IN favorable conditions and good educational process, a possible negative predisposition may not be realized, or may be corrected, “covered up” by the influence of neighboring awakened genes, and a positive predisposition, sometimes hidden, may manifest itself. Sometimes a person (child) simply does not know his capabilities, and categorically “giving up”, saying that “this ugly duckling will not grow into a swan” is dangerous.
Another danger, another risk is wasting time and energy on a person from whom nothing good can come of it. They say that anyone can become a genius, and in theory this is true. However, in practice, thirty years is enough for one, while another needs three hundred years, and invest in such problem people- unprofitable. R.M. Zagainov, an outstanding sports coach, is convinced that, despite the importance of the training system, achieving top results is, first of all, selection and talent. What is given to a person by nature.
If a girl was born brown-haired with green eyes and a “predisposition” to be overweight, then you can, of course, dye her hair and wear colored lenses: the girl will still remain a green-eyed brown-haired girl. But whether her “predisposition” will translate into fifty-large sizes worn by all her relatives largely depends on herself. And even more so, it depends on her whether by the age of forty, sitting in this fifty-large size, she will scold the state and her unfulfilled life (as all her relatives do) or will find herself many other interesting activities.
Can a person change, sometimes overcome, and sometimes improve his genetics? The answer to this question cannot be general, since this is also determined individually genetically. In general, it is correct to say that a child’s development is determined by his inclinations plus upbringing. However, for one child, from birth, 90% is determined by his inclinations and only 10% can be added by upbringing (a stubborn child), while for another, pliable child, he is almost like a blank slate, 10% of inclinations and 90% of what you put in through upbringing is what will happen. Both ratios are an innate characteristic of the child.
What is your or your child's ratio? You can only understand this experimentally by starting to work with your child (or yourself). Get started! Genes set opportunities; it depends on us how much we realize these opportunities. If you have good genetics, you can make them even better and pass them on to your children as the most precious gift. Our DNA remembers what kind of childhood we had, there are observations that habits, skills, inclinations and even manners are genetically transmitted. If you have developed good manners, beautiful manners, good voice, have accustomed yourself to a daily routine and responsibility, that is, there is a good chance that sooner or later this will become part of the genotype of your surname.
Genes determine our inclinations, our capabilities and inclinations, but not our destiny. Genes determine the starting point for activity - for some it is better, for others it is more difficult. But what will be done on the basis of this site is no longer the concern of genes, but of people: the person himself and those who are close to him.
Genetics can be improved - if not always in your individual destiny, then definitely in the destiny of your kind. Good luck with your genetics!
Scientists believe that intellectual abilities are determined by 50–70% by genes, and the choice of profession by 40%. 34% of us have a tendency towards politeness and rude behavior. Even the desire to sit for a long time in front of the TV is 45% a genetic predisposition.
The rest, according to experts, is determined by upbringing, social environment and sudden blows of fate - for example, illness. A gene, just like an individual organism, is subject to action natural selection . If, for example, it allows a person to survive more severe climatic conditions or wait longer physical exercise
– it will spread. If, on the contrary, it ensures the appearance of some harmful trait, then the prevalence of such a gene in the population will fall. During the intrauterine development of a child, this influence of natural selection on individual genes can manifest itself in quite strange ways. For example, genes inherited from the father are "interested" in rapid growth
the fetus - since the father’s body does not obviously lose from this, and the child grows faster. Maternal genes, on the other hand, promote slower development - which ultimately takes longer, but leaves the mother more strength.
Prader-Willi syndrome is an example of what happens when the mother's genes “victory”. During pregnancy, the fetus is inactive; After birth, the child experiences developmental delay, a tendency toward obesity, short stature, drowsiness, and impaired coordination of movements. It may seem strange that these apparently unfavorable traits are encoded by maternal genes - but it must be remembered that normally these same genes compete with paternal genes. In turn, the “victory” of paternal genes leads to the development of another disease: Angelman syndrome. In this case, the child develops hyperactivity, often epilepsy and delayed speech development. Sometimes lexicon
the patient is limited to just a few words, and even in this case the child understands most of what is said to him - it is the ability to express his thoughts that suffers. Of course, it’s impossible to predict a child’s appearance. But you can with a certain share
For each of its external and internal characteristics, the child receives two genes. These genes can be the same (tall, full lips) or different (tall and short, plump and thin). If the genes match, there will be no contradictions, and the child will inherit plump lips and tall height. In another case, the strongest gene wins.
A strong gene is called dominant, and a weak gene is called recessive. Strong genes in humans include dark and curly hair; baldness in men; brown or green eyes; normally pigmented skin. Recessive traits include blue eyes, straight, blond or red hair, and lack of skin pigment.
When a strong and a weak gene meet, as a rule, the stronger one wins. For example, mom is a brown-eyed brunette, and dad is blond with blue eyes, with a high degree of probability we can say that the baby will be born with dark hair and brown eyes.
True, brown-eyed parents may give birth to a newborn with blue eyes. Thus, genes received from a grandmother or grandfather could have an effect. The opposite situation is also possible. The explanation is that it turns out that for any trait we have, it is not just one gene from each parent, as was previously believed, that is responsible, but a whole group of genes. And sometimes one gene is responsible for several functions at once. So it’s responsible for eye color whole line genes that combine differently each time.
Hereditary diseases transmitted by genes
A baby can inherit from his parents not only appearance and character traits, but also diseases (cardiovascular, cancer, diabetes, Alzheimer's and Parkinson's diseases).
The disease may not appear if basic safety measures are taken. Tell your gynecologist in detail about serious health problems not only for you and your husband, but also for your close relatives. This will help protect the baby in the future. Sometimes absolutely healthy parents give birth to a baby with hereditary disease. It was embedded in the genes and appeared only in the child. This usually happens when both parents have the same disease in their genes. Therefore, if you are planning a child, according to experts, it is better to undergo a genetic examination. This is especially true for families in which children with hereditary diseases have already been born.
A weak gene may not be detected for one or many generations until two recessive genes from each parent occur. And then, for example, such a rare symptom as albinism may appear.
Chromosomes are also responsible for the sex of the child. For a woman, the chances of giving birth to a girl or a boy are equal. The gender of the child depends only on the father. If an egg meets a sperm with sex chromosome X, it will be a girl. If U, a boy will be born.
What else may depend on genes:
Gender – 100%;
Height – 80% (for men) and 70% (for women);
Blood pressure – 45%;
Snoring – 42%;
Female infidelity – 41%;
Spirituality – 40%;
Religiosity – 10%.
There are also genes responsible for the development of certain conditions, such as depression or a tendency to uncontrollable eating.
The level of mutations in men is 2 times higher than that in women. Thus, it turns out that humanity owes its progress to men.
All representatives of the human race are 99.9% identical in DNA, which completely rejects any basis for racism.
