Is a relationship between second cousins ​​possible? Love between brother and sister. Vivid life examples

Society has a negative attitude towards incest, and in many, especially Western, civilizations it is strictly prohibited. However, a study by Icelandic experts showed that consanguineous marriages lead to increased fertility. However, this observation does not apply to siblings and cousins ​​- their children, as a rule, die earlier than others and show a reduced ability to reproduce.

Incest

In Russian, incest, or incest, is usually used to describe sexual relations only between close relatives, the circle of which is limited to the relationships of father, mother, daughter, son, sister and brother. In relation to the relationship of half-siblings (from the same father and different mothers or from the same mother and different fathers), the term is used less confidently.

In Western literature, incest is sometimes also called sexual relations between first and second cousins, but in the Russian tradition they are considered consanguineous relations, but not incest.

It has long been known that marrying a representative or representative of another family tree is more beneficial, since in this case the offspring receives fresh genetic material, the dominant genes of which subsequently prevent recessive genes from appearing, causing hereditary genetic diseases. Members of royal families, for example, suffered from such diseases.

However, it turned out that incest in some cases can be even more profitable than marriage outside the family.

Incest in the past was widespread, especially among the rural population, where the search for a betrothed or a bride from someone else's family often meant a long, expensive and tedious tour of the surrounding villages and villages. Nowadays, marriages between cousins ​​in the first row of the family tree are common in eastern countries, where it saves on dowries and consolidates family resources.

Attempts to assess the impact of such marriages on the health and prosperity of the nation have been made before, but the interpretation of the results of these studies has always been complicated by the presence of social and economic factors. As the author of the study, Kari Stefanson, notes, her team was lucky in this regard, since the Icelandic nation lives on an island and demonstrates high homogeneity both culturally and economically.

Scientists analyzed one hundred and sixty thousand married couples who lived between 1800 and 1965. results The work was published in the latest issue of Science.

The study confirmed the well-known fact that mixing the blood of close relatives leads to the birth of children who are more prone to illness and early death, and also less capable of procreation. Although such families produce more children than married distant relatives, this advantage turns out to be illusory: children are often born sick and are unable to have children, or even die before reaching childbearing age. As a result, already in the next generation this line begins to lose.

However, as it turned out, married couples formed by relatives through the third and fourth generation have the largest number of grandchildren among all others.

This may indicate not only increased fertility of children in such marriages, but also, to a large extent, excellent genetic health. Thus, marriages between relatives of the third row of the family tree turn out to be the most beneficial for increasing the size of the nation and maintaining health.

Apparently, genetic similarity has a certain importance for future childbearing. For example, the world knows such a dangerous phenomenon as Rh incompatibility, when one of the partners has a positive Rh factor, and the other has a negative one. If the embryo developing in the mother’s womb inherits the Rh factor from the father, then Rh incompatibility can cause an immune conflict between the mother and the fetus. As a result, the mother’s body will launch a mechanism to fight the fetus as a foreign object, which can result in congenital diseases or even lead to the death of the newborn.

Alan Bittles, a human geneticist from Australia, believes that there is a certain optimum in the genetic relatedness of people, allowing them to produce the most genetically healthy and numerous offspring.

However, the study of the Icelandic population cannot answer the question of how much this optimal degree of relatedness is individual and how it depends on other factors. Who knows, maybe in the East, where consanguineous marriages are more common, this state of affairs is more beneficial for the entire population? Or maybe in small Iceland it is simply difficult to find couples who are more distantly related to each other than the third and fourth generation?

Can love conquer all? If you don’t think for a long time, the answer to this question will definitely be romantically positive. But if we recall some historical and modern prohibitions and barriers, then the unambiguousness of such an answer may be called into question. For example, sometimes people from different social classes simply cannot be together, and in other cases love disappears under the influence of time and distance. But there is another type of prohibition related to love and, accordingly, to marriage. This is a ban on marriage between relatives. At the same time, the greatest controversy is about the marriages of cousins. Why is this so, and are first cousin marriages really undesirable?

Why do marriages between cousins ​​cause the greatest resonance in society? Everything is very simple here. Marriages between first-degree relatives are a priori prohibited, and almost everyone agrees with this. Marriages between distant relatives, although not particularly approved, are not strongly condemned either. But marriages between cousins ​​are precisely the front line on which battles constantly take place between scientists, doctors, church workers, and, most importantly, between the relatives of those who want to enter into such a marriage.

How was it before?

History contains many facts of related marriages, and the reasons for their conclusion were very different. Some of the most significant reasons were considered political and financial. Royal dynasties previously did not allow outsiders into their circle, and marriages were concluded exclusively between persons from royal families. It is clear that there were much more ordinary people who did not belong to royal families, but the number of representatives of royal dynasties did not always make it possible to find worthy spouses without any degree of kinship.

In addition, quite often the reason for marriages between relatives was the idea of ​​some nationalities that money should not leave the family.

There were also other reasons for consanguineous marriages, such as reluctance to mix blood. Aristocratic families who were careful about the history of their surnames were distinguished by such ideas about an ideal marriage.

What do scientists say?

Now, after many hundreds of years, modern scientists say that it was marriages between relatives that became the reason for the extinction of the dynasty of the Egyptian pharaohs. After all, geneticists constantly talk about the increased likelihood of all kinds of physiological abnormalities in the descendants of those who enter into related marriages. And a clear confirmation of this, according to scientists, are the same royal dynasties, the children in which suffered much more often from hereditary anomalies and were generally less viable compared to other children born in marriages between people who do not have family ties.

In addition, in contrast to the theory about the harmfulness of mixing blood, modern scientists cite another theory, according to which the more blood is mixed, the more healthy, beautiful and mentally developed the offspring will be.

In modern society, marriages between cousins ​​are not so common. However, different nationalities have different attitudes towards this phenomenon. In many Asian countries, as well as in small settlements where residents have little interaction with the rest of society, marriages between cousins ​​are either encouraged or almost inevitable. There are no legal prohibitions on such marriages in Europe. But in America, cousins ​​cannot always officially become husband and wife, since such marriages are prohibited in 24 American states, and in another 7 states they are possible, but subject to mandatory conditions, for example, passing a genetic examination.

Marriages between cousins: possible risks

In addition to family and religious stigma, there are also certain medical risks associated with having offspring from first cousins.

These medical risks are explained very simply. The fact is that relatives are much more likely to have the same hidden gene changes. For both women and men, such a hidden gene change does not pose any danger (that’s why it’s hidden). But if such a woman and man, who have the same ancestors, think about their offspring, then the likelihood increases that their child’s gene change will not be hidden.

This is why marriages between first cousins ​​must be medically approved. Of course, it is impossible to completely exclude the possibility of the coincidence of two identically altered genes, but it is still possible to reduce the risk of genetic diseases and anomalies in the offspring. During a conversation with potential parents, geneticists carefully examine the incidence of several previous generations, establish the percentage of hereditary diseases, and also determine the nature of the relationship between a man and a woman.

Based on the results of such genetic studies, it is determined how likely it is to have offspring with genetic abnormalities.

Latest Scientific Research

Some modern scientists have ceased to be categorical about such a phenomenon as marriages between cousins. And the reason for this was scientific research, during which it turned out that the risk of genetic abnormalities in a child born from cousins ​​is only a few percent higher.

But in any case, without conducting a genetic examination, doctors do not advise cousins ​​to think about having children together.

The problem of marriages between cousins ​​affects many different aspects, both moral, spiritual and physiological. It is hardly possible to condemn people who take such a step, since this is only their choice, and no one has the right to persistently influence it. But each of us will have our own opinion on this issue, and we also have the right to it.

Consanguineous marriages in Rus' were not encouraged either in the pagan or Christian periods. Although, of course, they began to be regulated more strictly already in the era of Christianity.

Kinship marriages among the ancient Slavs

The ancient Slavs already knew that incest could lead to unhealthy offspring. Therefore, they prohibited marriages between direct relatives - for example, parents and children, brothers and sisters, grandparents and grandchildren. Our ancestors said: “Don’t marry those with whom you eat together.” And they ate together, as a rule, with close relatives with whom they lived in the same house.

True, sources that appeared during the time of Christianity claim that the Slavs practiced close incest. Thus, the chronicler Nestor in “The Tale of Bygone Years” reports that the Drevlyans, Radimichi, Vyatichi and Northerners were “shamers before their fathers and daughters-in-law,” and the historian Smirnov claims that “in ancient times, brothers had conjugal rights over their sisters.”

But at the same time, the ancient Slavic custom of “kidnapping” the bride by the future groom is widely known. “...Exogamous prohibitions that appeared in primitive society were also in effect among the Eastern Slavs, which is proven by the abduction of the bride itself, which had no meaning in relations between close relatives,” says Omelyanchuk, author of the work “Marriage and Family in Ancient Rus' of the 9th-13th centuries” .

Most likely, in the pagan period, people who were more distantly related to each other, for example, uncles and nieces, cousins ​​and second cousins, could marry each other.

Byzantine marriage norms

With the advent of Christianity, marriages began to be concluded according to Byzantine law. Marriages between relatives in both ascending and descending direct lines were prohibited: “We command those who forbid marriage to enter into the slaughter and those going out into the infinite, the brother will forbid unless the marriage is legal, for no one can marry his wife or grandchildren.”

Collections of norms of Byzantine law for the 8th and 9th centuries also spoke of restrictions on marriages along the lateral line, in particular, the prohibition of marriage unions not only between cousins, but also between their children. That is, a ban was introduced on the creation of a family by people who were in the fourth, fifth and sixth degrees of consanguinity. But even marriages in the seventh degree of kinship were recognized by the church as undesirable.

Thus, in 1038, Patriarch Alexy Sudit issued a decree entitled “On Quiet Forbidden Brothers,” which clearly prohibited marriages between people in the seventh degree of kinship. But at the same time, the clergy did not insist on the dissolution of those related marriages that were concluded earlier. In this case, the spouses were only forced to church repentance. However, later, in the 12th century, the Byzantine emperor Manuel Komnenos completely banned such marriages, declaring them “unclean, incestuous and subject to dissolution.”

Thus, only marriages no closer than the eighth degree of kinship were allowed. This also applied to illegal children.

What types of kinship prevented marriage?

It is curious that, in addition to blood relationship, marriages based on property were not allowed. For example, half-brothers and sisters who did not have common parents, or blood relatives of two spouses (say, the wife's brother and the husband's sister) could not marry each other. True, in some cases the restrictions were less strict, and such marriages were often looked at with a blind eye, especially when it came to distant relationships. By the way, relationships that arose as a result of betrothal, and even relationships between relatives of two divorced spouses, were equated to property.

There was also a so-called kinship by adoption. According to existing canons, marriages were prohibited not only between adoptive parents and adopted children who did not have blood ties with each other, but also, suppose, between an adoptive parent and a close blood relative of the adopted person, such as his wife, mother, sister, aunt, daughter or granddaughter.

Finally, there was the concept of spiritual kinship. It arose either between godfathers or mothers (godfathers), or between one of the godfathers and his godson. It is interesting that such a relationship was equated to blood, and the Byzantine Eclogue forbade “those who are united by the bonds of holy and saving baptism to marry.”

It was also forbidden for godparents and close relatives of godchildren to marry, or vice versa. In the first half of the 16th century, the Austrian diplomat Sigismund von Herberstein in his “Notes on Muscovy” mentions: “They enter into marriage in such a way as not to touch the fourth degree of kinship and property. They consider it heresy for brothers to marry their own sisters, just as no one dares to marry his brother-in-law's sister. Further, they observe very strictly that those between whom there is a spiritual relationship through baptism do not unite in marriage.”

Lifting the ban

Despite this, in Rus' marriages continued to take place between those who were in the fifth, sixth and seventh degrees of relationship. And, as a rule, they were not declared invalid, since no one during the wedding declared that the bride and groom were related.

In 1810, the Synod lifted the ban on marriages based on kinship and property up to the seventh generation. Now it was possible to marry those who were related beyond the fourth degree, as well as those who were related to each other beyond the second degree.

Moreover, ancient Russian laws created obstacles for marriages between representatives of noble noble families. Thus, members of the Romanov royal family very often married their relatives, and in the aristocratic environment, marriage between cousins ​​was not at all uncommon.

It has long been known that marriages between close relatives are fraught with poor heredity.

This opinion emerged from life practice.

A large number of noble families died out in ancient times because they did not avoid incest.

Religion and science do not approve of such things at all.

Simply because there is a high risk of children being born still or with major abnormalities. People will degenerate.

That is why in our country there is a law that does not allow close relatives of the first generation to register relationships. But, the restriction does not apply to marriage between cousins. This is due to a lower likelihood of the occurrence of pathologies and their offspring.

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What the law says

In ancient times, it was customary to tie bonds only with relatives, for the purity of the family.

Back then people didn’t think about genetics.

Currently, registering relationships between first-degree relatives is prohibited and in some countries is even considered a crime.

In our country, on the basis of Art. 14 IC you cannot enter into marriage relations with close people:

• mother, father and their offspring
• grandparents and grandchildren
• siblings
• adoptive parents and adopted children

But, employees of the civil registry office do not require additional evidence indicating the absence of relationship.

Important! Marriage between adoptive parents and adopted children is allowed in case of cancellation of official adoption.

As for more distant relatives, the law does not impose restrictions on them. This includes first and second cousins. And also uncles and aunts. In general, representatives of a more distant relationship than the first generation.

Marriages between cousins ​​are permitted by Russian law, but citizens react negatively to such marriages.

Even temporary registration between first-degree family members is unacceptable. Even a pregnant woman cannot sign with a relative. Although, in essence, what is the point of this?

However, if you rely on practice, in fact such a marriage can be concluded. Because the law does not oblige civil registry office employees to confirm or deny the presence of family ties. When a couple is silent about the existence of such connections, they will be signed, but if this fact is clarified, the marriage will be declared legally invalid.

Important! In Russia, importance is attached only to officially registered relationships.

It's no secret that everyone has the opportunity to simply live in civilian clothes. When people strongly desire to be together, the lack of official registration will not hinder them. But there is another side to the issue and this is genetics.

For decades now, people have understood that intimate relationships between family members can result in children with various types of disabilities.

This is due to the high probability of encountering the same gene in their offspring.

This will not affect a woman or a man.

But children born by them will most likely have serious pathologies.

Therefore, in such relationships, in addition to condemnation, you can also encounter great unpleasantness. Sometimes cousins ​​come to the decision to build a social unit. When taking this step, it is better to play it safe and undergo a medical examination.

The doctor finds out the percentage of hereditary diseases, establishes the degree of relationship, as well as the likelihood of having sick offspring. In most cases, pathologies do not occur in distant relatives.

If we take into account close relationships, then here are the following percentages of the occurrence of pathologies:

• the probability of a stillborn baby being born is 24%
• death of a child at an early age - 34%
• risk of deformity - 48%

Before building a relationship with a relative, you should think about the risk of giving birth to patients. The law does not establish a restriction on the registration of relationships between first cousins, since such relationships carry less risk for offspring.

Results of the latest scientific research

Modern scientists have ceased to be critical of marriage between cousins.

This is due to the results of recent studies.

Of course, there is a percentage of pathologies occurring, but it is very small. However, before entering into such a relationship, scientists recommend conducting a genetic test.

This will help avoid consequences, that is, the birth of defective children. Such relationships affect many aspects, mainly social.

However, how can you judge people who made their own decisions? No one has the right to insist otherwise. It is enough to simply mention the possibility of pathology.

According to scientific research, the risk of having a handicapped child from cousins ​​is only 1.7% greater than when a baby is born in an ordinary family.

In fact, the risk of having children for other categories of people is much higher than this. For example, the birth of a baby in a family of alcoholics or women over 40 years old. Although such marriages are not controlled.

It turns out, from a scientific point of view, marriage between cousins ​​does not have global consequences. Only a small percentage of such families can produce children with pathologies.

In life there are many people born from cousins:

• Alexander Sergeevich Pushkin, for example, was born from the relationship of his uncle and second cousin.
• The no less famous Charles Darwin had a cousin wife. They had ten children. True, three died while still young, but many of those who remained achieved great success in society.
• What can we say about Cleopatra? She was the daughter of her brother and sister. Egyptian traditions did not prohibit such marriages; on the contrary, they did not welcome incest. The queen herself was a true beauty and more than once married her relatives.
• Rudy Julian transformed New York into a metropolis. Before Julian became mayor, he represented the prosecution in court. Not without his participation, gangster John Gott spent the rest of his life. Julian married his cousin, although they divorced after 14 years.
• In the eighties, Greta Skaki was a sex symbol. Her cousin Carlo could not resist her either. This is a completely normal family. They had a son. Their relationship caused a real stir, which is why Greta's career ended.
• Everyone knows Einstein, who is simply a genius. He developed a huge number of physical theories and earned a Nobel Prize. His wife was his second cousin Elsa.
• The famous former president of Iraq had many wives, one of which was his cousin.
• One of the famous bandits of the Wild West, Jesse James, had a cousin as his wife. Their family had two completely healthy children.

Despite the fact that the percentage of defective children between cousins ​​is low, the United States has banned such marriages. This has greatly impacted abortion statistics. Scientists are not sure that this discrimination will end soon, but it is unlikely that anything will prevent people from living together if they want it themselves.

Scientists have proven that children born from relationships between cousins ​​have almost equal chances of developing pathologies, like any other babies.

First of all, countries that ban such marriages pursue social goals rather than medical ones.

All scientists are confident that such laws have no basis. Simply because the probability of an unhealthy offspring appearing in such families exceeds the standard situation by only 2%.

But no one takes into account that parents can be people over forty years old. In addition, this deviation includes drug addicts and alcoholics. And, as you know, they are more likely to give birth to a sick person.

One of the most important stages in life is the creation of a separate unit of society. All civilized countries have introduced restrictions on the registration of relations between family members belonging to the first generation. Russia is no exception.

In the video you can see what will happen if a brother and sister have children:

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L. 3. KAZANTSEVA, Doctor of Medical Sciences
V. P. VETROV, Candidate of Medical Sciences

The young people first met at some family celebration, liked each other, began dating, and decided to become husband and wife.

And then the relatives were alarmed: after all, they were cousins! Doesn't this threaten their future children with something bad?

The young man’s parents reacted more calmly to the upcoming marriage: they knew a family where the spouses were related in the same way, which did not prevent them from giving birth to two healthy boys. The girl's parents objected: they knew an example of the opposite property.

How can we be our lover? Discouraged and upset, they came to the pediatrician for advice. He recommended that they seek medical genetic consultation. But genetic specialists were not able to answer them right away: they had to come for consultation more than once.

The problem is really complex. It has long been noted that children of related spouses suffer from hereditary diseases more often than children of unrelated married couples.

A striking historical example of the unfavorable effect of consanguineous marriages on offspring is provided by royal dynasties. After all, as the popular song says, “no king can marry for love.”

Marriages of crowned heads were very often concluded for political reasons, and the choice of brides and grooms was limited to a narrow circle of reigning houses that had previously become related to each other.

The sad consequence of the chain of such related marriages was an increase in the number of hereditary anomalies, up to the birth of defective and even non-viable children.

According to experts, it was for this reason that the dynasty of the Egyptian pharaohs, in which marriages between siblings took place from generation to generation, died out.

Characteristic in this regard is the history of the House of Habsburg, where members of the royal family more than once married each other: thus, Philip II was married to a cousin in his first marriage, and a niece in his second; his son Philip III is based on his cousin, Philip IV is based on his niece.

The descendants of these kings are known to be pronounced oligophrenics, incapable of any activity.

These days, consanguineous marriages are becoming more rare than they once were: in Europe and North America they do not exceed one percent; in Asia their number is higher, but even here there is a tendency towards their decrease.

Peculiar closed communities have long been formed in mountainous, inaccessible places, on remote islands. The long-term stability of the population and its small migration made consanguineous marriages here almost inevitable.

Similar isolates have survived in some places to this day. They exist, for example, in the mountainous regions of Switzerland and in South America. But the most surprising thing is the existence of closed religious communities in multimillion-dollar London, as well as in the USA.

These include, for example, the Mennonite sect (eight thousand people), which traces its origins to a few emigrants who arrived in North America back in the 18th century.

Researchers who studied the incidence of disease in such isolated communities with a high percentage of consanguineous marriages invariably noted a higher than usual percentage of hereditary diseases and malformations there.

Mental retardation, speech defects, hereditary deafness, and metabolic diseases were more often recorded.

Why does consanguineous marriage become dangerous for the offspring even in cases where both spouses seem to be completely healthy?

The fact is that there is a group of hereditary diseases caused by pathological changes in genes responsible for certain signs or characteristics of the body.

Moreover, this is characteristic: one altered gene does not yet manifest itself in any way, its carrier himself remains healthy, and his child is also not at risk of a hereditary disease.

But if, by chance, two carriers of similar identically altered genes become spouses, a situation arises that is dangerous for the offspring.

True, even in such a marriage the development of a hereditary disease is not necessary. And here's why: in carriers of altered genes, only half of the germ cells are marked by these changes.

It is possible that the embryo will begin to develop from two normal cells, and then the child will be born healthy, since he did not receive the altered gene from his parents.

The second option: the embryo develops from a normal cell and a cell carrying an altered gene. Then the child will also be healthy, but will become the same hidden carrier as his parents.

Finally, the third option: both germ cells (male and female) carry the altered gene. In this case, the child will be born sick. What was a hidden defect in his parents becomes obvious in him.

The marriage of two healthy people with the same hidden gene change is rare. But the likelihood of such a truly fatal meeting increases if blood relatives marry, that is, people who have one or more common ancestors, from whom both could inherit the altered gene.

The closer the relationship, the greater the risk that the spouses may have the same genes as their common ancestor. This is largely why incest marriages, that is, marital unions of first-degree relatives (parents and their children, siblings), are prohibited by the legislation of most countries.

There are usually no legal prohibitions on marriages of more distant relatives, since they are less risky for offspring. However, in some countries there are restrictions for such marital unions.

There are even laws that are completely absurd from the point of view of genetics, for example, the unconditional prohibition of the marriage of a nephew with an aunt, although she may not be a blood relative, but only the wife of an uncle, or the prohibition of marriage with a stepmother, daughter or son of a spouse from another marriage, with... . mother-in-law and even his wife’s grandmother (!!!).

Naturally, such laws can be viewed as a curiosity.

In our country, only incest marriages are prohibited, including marriages between half-brothers and sisters (from different fathers or mothers).

First cousins, second cousins, and other distant relatives can legally marry. But the young people did the right thing by turning to a doctor for advice. Having found out what their common relatives were sick with, a specialist can more easily determine whether there is a danger of having sick children.

Pedigree of the N. family, the founders of which were a healthy woman (white figure) and a man - a hidden carrier of the altered gene (black and white figure).
In the third generation, a marriage took place between cousins, hidden carriers of the altered gene.
Among their children, two were born sick (black figures), two boys and two girls became hidden carriers of the altered gene (black and white figures), and only one boy and one girl were born completely healthy (white figures).

Of course, the accuracy of the forecast largely depends on the completeness of the information it will have. The experience of medical genetic consultations shows that rural residents usually know their ancestry better, city dwellers - worse.

And it’s not bad to know it out of interest in one’s own “roots,” but this information becomes absolutely necessary when the need for medical genetic consultation arises.

It is important to collect data on as many relatives as possible; What matters are family ties “horizontally”, that is, other siblings, second cousins, and also “vertically” - parents, uncles, aunts, grandparents, great-grandparents, and if possible - even further in depth. It is important to know what illnesses these people had, how long they lived, and what they died from.

In addition to analyzing such data, doctors have other research methods that allow them to determine the degree of risk. In particular, tests have recently been developed to help identify latent carriage of the altered gene.

As we see, the question of whether the marriage of cousins ​​threatens the health of their future children has to be answered differently in each specific case. And only expert advice can be authoritative here.