Cloning: pros and cons. Arguments against human cloning. Human cloning: pros and cons Human cloning biological
The science
Man has been interested in cloning since ancient times and this is reflected in many literary works and films. Although human cloning is inherently considered unethical, ethical issues regarding whether it is right or wrong often involve subjective opinion and emotion.
The concept of cloning involves removing the nucleus from an egg and placing it into another fertilized egg in which the nucleus has been removed. This core, in a new location, controls the development of the whole organism. Although cloning is a natural process in some organisms, such as armadillos, cottonwoods and aphids, it can also be done in humans.
Here are 9 arguments that shed light on the unethical nature and development of new technologies for safe and successful human cloning.
1. Social anxiety
One of the biggest problems with human cloning is that it creates a unique and challenging social confrontation. If a person clones himself and raises a child as his own, then this creates a strange situation. Instead of being the clone's father, he becomes the clone's brother. Also, in society, clones find themselves in a very awkward position. How should we perceive them? When a new family member is added, he is related to the rest of the family, and clones appear out of nowhere. Relationships with other family members are a simple concept, but not a reality. Such social awkwardness leads to psychological obstacles in the development of the clone.
2. Forced psychological development
In the book Boys from Brazil, 94 clones of Adolf Hitler are created in different parts of the world so that each of them kills his father to recreate the same circumstances that would lead to the emergence of a new Fuhrer. This more than sufficiently confirms that cloned humans will be samples of their nuclear donors. They will have a different life because their life can be measured. They will be subjected to tests that they must pass because that is what originally happened. This limits their psychological and social development.
3. Freedom of choice
Whenever a stunning discovery comes to light, it is opposed by the people, the church, the government, etc. This happens because a person has always been afraid of change. Judging whether human cloning is wrong depends on the person's views. With the increase in individualism in human society, the choice remains with the individual.
4. Reification of man
If a person can be grown in a laboratory like a vegetable, this undermines the very purpose of birth. The love, care and pain that a mother goes through to give birth to a child represents a person. It is part of our identity as living organisms. The idea of man as an object that can be produced destroys his individuality.
A child born through cloning is not unique, it is an image of a nuclear donor and has no individuality. Such a child will always be perceived as part of a product that can be produced again and again.
Humans are endowed with intelligence, but using intelligence to produce a "sub-human" is an abuse of power. Will such people be treated with the same respect and dignity in society?
5. A refuge for many
What if the smartest man on earth married the most beautiful woman? Their total gene pool will be represented by genes of excellent quality. Their children will have everything they want and everyone will envy them. Now add infertility to the mix. This makes it more difficult because if they cannot conceive, they will need to adopt.
What if human reproductive cloning progressed to such an extent that it became completely it is safe to give birth to your children while being infertile? For people who cannot respond to infertility treatment, reproductive cloning will be a real gift. This will help them avoid many problems, including psychological stress associated with adopted children. This will allow them to live just like everyone else.
Cloning also provides an opportunity for gay couples to have a normal family. They will be able to find a child who can grow up and be raised like in an ordinary family.
6. Unsafe procedure
Dolly, the most famous clone sheep, lived for 6 years and gave birth to 5 healthy lambs. She died of lung cancer, which is quite common among sheep. Despite the fact that the circumstances of her death may seem ordinary to many, not everyone agrees with this opinion. Dolly was predicted to have a life expectancy of 11-12 years, but she died prematurely. It is believed that the possible cause of premature death was that her genetic age was 6 years. Since it is virtually impossible to clone a newborn, clones will always suffer from this anomaly.
Thus, the development of clones can become destructive, leading to the death of many clones, which can even be considered murder. The technology has not yet developed to the point where clones can be successfully conceived, and it may be better this way.
7. Down a dangerous path
Movies and books often show dangerous methods of genetic engineering. If human cloning is encouraged and accepted, who can guarantee that new technologies will not lead to a dangerous scenario? Reproductive cloning is on the verge of a very dangerous path that can lead to all sorts of destruction.
8. Healing agent
Humanity has always dreamed of a miracle cure that would cure all diseases, or at least something similar. Cloning is one of the closest means to this idea.
Cloning gives the ability to grow human body parts using host DNA. Such body parts can be used to replace existing but unusable parts. It is also possible to clone certain organs and replace diseased organs with them. Many people die from organ failure, or lose organs in accidents, or are born with defects. These people could be cured through cloning
9. The Man Playing the Role of God
After human cloning became a common idea, the Bible and Quran were quoted as sayings that were interpreted against cloning. The development of cloning is the same as becoming God. Man creates life using cloning, developing some traits and eliminating others. The creation of life, which was the privilege of God, may be carried out in laboratories and test tubes.
Although there are both supporters and opponents of human cloning, it is believed that the idea of human cloning will do more harm than good and therefore the study and development of this issue should be suspended, at least until the present moment.
MOSCOW, October 26 – RIA Novosti. Valery Spiridonov, the first candidate for a body transplant, talks about how modern technologies for cloning living organisms originated and discusses the consequences of their appearance for humanity.
Key of Life
The beginning of research into alternative bioreproduction dates back to 1885, when the German scientist Hans Driesch began studying methods of reproduction, experimenting on sea urchins and other animals with large eggs. In 1902, he managed to raise two full-fledged sea urchins by dividing one embryo into two halves during the first stages of its growth.
A fundamentally new cloning method was developed in the 1940s by Soviet embryologist Georgy Lapshov. He isolated the nucleus of a non-reproductive cell and introduced it into an egg with a previously extracted nucleus. This cloning method is called "nuclear transfer".
American embryologists were later able to conduct similar experiments with frog tadpoles. And in 1996, news spread throughout the world about the successful cloning of Dolly the sheep. It was the first mammal cloned from the cells of an adult.
Subsequently, scientists tried to clone many more animals: mice, pigs, goats, cows, horses, rats and others. In parallel with this, new genetic engineering techniques were created that make it possible to change the DNA of an embryo during cloning and do other fantastic things that are commonplace in science and medicine today.
© AP Photo/Stephan Moitessier
© AP Photo/Stephan Moitessier
However, the purpose of such experiments was not only to recreate a population of rare animal species, but also to test cloning technologies and methods to create a copy of a person or his individual tissues.
Copies are illegal. Legislative regulation in Russia and the world
Most countries around the world have temporarily banned cloning. It is primarily due to ethical issues, as well as the imperfections of available technologies. When scientists carry out the cloning process, they simultaneously create hundreds of embryos, most of which do not survive to the implantation stage.
In addition, observations of the length of telomeres, the terminal sections of DNA, show that clones should have a shorter life expectancy than their “parents”, which, however, has not yet manifested itself in observations of actually living clones, despite shorter telomeres than in animals of similar age conceived naturally.
In Russia, since April 19, 2002, the federal law “On a temporary ban on human cloning” has been in force. This document expired in 2007. The moratorium was then extended in 2010 for an indefinite period until a law establishing the procedure for the use of technologies in this area came into force. However, the law does not prohibit the cloning of cells for research purposes or for transplantation.
Despite resistance from politicians and the public, the first laboratory studies and experiments on human embryos have recently been carried out in China, the USA, the UK and the Netherlands. In other countries of the world (for example, in France, Germany and Japan), such experiments still remain outside the law.
© AP Photo/Camay Sungu
© AP Photo/Camay Sungu
If we consider this issue from the point of view of religion, then we can say that any type of cloning is unacceptable for representatives of almost all faiths of the world.
At the moment, there is no reliable information about human cloning experiments conducted. The US National Human Genome Institute, one of the main research centers working in this direction, distinguishes three types of cloning: gene, reproductive and therapeutic.
Gene cloning
Cloning of genes or DNA segments (as defined by the University of Nebraska) is a process in which DNA is extracted from cells, cut into pieces, and then one of those pieces containing a gene is inserted into the genome of another organism. .
© AP Photo/Elaine Thompson
© AP Photo/Elaine Thompson
As a rule, its role is played by various microbes, whose DNA is much easier to manipulate than the genome of humans or other multicellular living creatures, in which the genetic material is packaged inside the nucleus, isolated from the rest of the cell.
Having received several hundred of these microbes with “cloned” foreign DNA, scientists observe how their life activity has changed and select those bacteria that contain interesting genes that can, for example, make plants invulnerable to attacks by various pathogenic fungi or protect them from attacks by pests.
Similarly, “cloning” human genes into microbial DNA allows molecular biologists to search for the causes of various genetic diseases and create gene therapies that can combat them.
Therapeutic cloning
Embryonic stem cells and their analogues, made from “reprogrammed” skin or connective tissue cells, can become virtually any type of cell in the body. This feature allows them to recreate tissues and organs that are compatible with the recipient’s immune system.
In Russia this process is called cell reproduction. It is similar to reproductive cloning, but in this case the growth period of the culture is limited to two weeks. After 14 days, the process of their reproduction is interrupted, and the cells are used in laboratory conditions. For example, to replace damaged tissues. They can also serve to test therapeutic drugs.
Artificial skin is already grown using this method in the UK, and full-fledged bladders are created in the USA.
Reproductive cloning
In the future, cloning could completely solve the problem of infertility - a striking example of this was the famous sheep Dolly.
The source of genetic material was the cells of a deceased sheep, another sheep became the egg donor, and a third animal played the role of a surrogate mother. Of the 277 cells, only 29 developed into an embryo, only one of which survived.
Despite the uniqueness of the experiment and a scientific breakthrough for that time, its results were criticized.
The main reason is that the experiment was not pure from a genetic point of view. In addition to nuclear DNA, part of the genome is contained within the so-called mitochondria, the cellular "power stations". In this case, Dolly inherited mitochondria not from her “genetic” mother, but from an egg donor, which is why she cannot be called a 100% clone. The question arises: is it in principle possible to create an ideal copy of any person or animal?
Are there no absolute clones?
Even if a clone is initially genetically identical to the original, its similarity will inevitably decrease over time. This will be reflected in both external and internal characteristics. Gene therapy using a set of embryonic genes rejuvenated the skin and some organs of elderly mice, paving the way for the creation of rejuvenation techniques for human cells.
In particular, new random mutations constantly arise in the genome of humans and animals, due to which the clone and the original will become different in the first seconds of their “separate” existence. Even natural “clones”, identical twins, initially have several dozen different mutations, and their number gradually increases after their birth.
Moreover, if we remember physics, we will notice that the very laws of quantum mechanics prohibit the existence of ideal copies of any objects.
Uncertain future
However, science does not stand still, and over the past decades, cloning techniques for both genes and organisms have become much safer and more reliable, reducing the likelihood of unsuccessful cloning or errors occurring when transplanting DNA into a foreign organism.
For example, the emergence of cell “reprogramming” techniques allows scientists today to obtain large quantities of stem cells and even grow full-fledged embryos without sacrificing other embryos for this. For now, such cells are used only in laboratories, but in the future they may find their place in the treatment of Parkinson’s diseases, Alzheimer’s diseases, the consequences of strokes, blindness and many other health problems.
The improvement of biotechnology and the accumulation of scientific knowledge in the field of genetic engineering opens up new opportunities for humans: the elimination of genetic diseases, biocompatible transplantology, an alternative solution to infertility problems and, possibly, the birth of children with given parameters.
There are three types of cloning: gene cloning, reproductive cloning and therapeutic cloning.
Gene cloning produces copies of genes, the most common and common type of cloning performed by researchers at the National Human Gene Research Institute (NHRI).
NHH researchers have not cloned any mammals, and does not clone humans. Typically, cloning technologies are used to make copies of the genes they wish to study. The procedure consists of inserting a gene from one organism, often referred to as "foreign DNA," into a courier's genetic material called a vector. Examples of vectors include bacteria, yeast cells, viruses, and so on; they have small circles of DNA. Once the gene is inserted, the vector is placed under laboratory conditions that encourage it to multiply, ending with the gene being copied as many times as needed. Gene cloning is also known as DNA cloning. This process is very different from reproductive and therapeutic cloning.
Reproductive and therapeutic cloning share many of the same techniques but are created for different purposes.
Therapeutic cloning is used to create a cloned embryo for the sole purpose of creating embryonic stem cells with the same DNA as the donor cell. These stem cells can be used in experiments aimed at studying the disease and inventing new methods for treating the disease.
The richest source of embryonic stem cells is the tissue formed during the first five days after the egg begins to divide. At this stage of development, called the blastoid period, the embryo consists of a group of about 100 cells that can become any type of cell. Stem cells are collected from cloned embryos at this stage of development, ending with the destruction of the embryo while it is still in the test tube. Researchers hope to grow embryonic stem cells, which have the unique ability to transform into virtually any type of cell in the body, in a laboratory that can be used to grow healthy tissue to replace damaged tissue. It is also possible to learn more about the molecular causes of disease by studying embryonic stem cell lines from cloned embryos obtained from animals or humans with various diseases.
Many scientists believe that stem cell research is worthy of the highest attention, since they can help cure a person from many diseases. However, some experts are concerned that stem cells and cancer cells are very similar in structure. And both types of cells have the ability to spread indefinitely, and some studies show that after 60 cycles of cell division, stem cells can accumulate mutations that could lead to cancer. Therefore, the relationship between stem cells and cancer cells must be studied as much as possible before using this treatment technique.
Along with this, therapeutic cloning raises another question related to the technology of its implementation. Currently, the only feasible technology is cloning, which involves growing a clone to a certain extent in vivo. Naturally, this does not apply to humans - a woman cannot be considered as an incubator of therapeutic material. This problem is being solved by the development of equipment for growing embryos in vitro. However, the problem of “killing” the embryo remains. Since when does a fetus become a person? There is an opinion that a new person arises at the moment of conception (in the case of a clone, at the moment of nuclear transplantation). In this case, the use of the embryo for growing transplants is unacceptable. It is objected to this that, until a certain period, the embryo represents only a collection of cells, but in no way a human personality. To overcome this problem, scientists are trying to start working with the embryo as early as possible.
Genetic engineering is a highly regulated technology that is largely studied today and is used in many laboratories around the world. However, both reproductive and therapeutic cloning raise important ethical issues because these cloning technologies can be applied to humans.
Reproductive cloning produces copies of entire animals.
It also provides the opportunity to create a person who is genetically identical to another person who once existed or currently exists. This is to some extent contrary to long-standing religious and social values about human dignity. Many believe that this violates all principles of individual freedom and individuality. However, some argue that reproductive cloning could help childless couples make their dream of becoming parents a reality. Others see human cloning as a way to stop the inheritance of a “harmful” gene. But we must remember that with this type of cloning, stem cells are taken from the embryo located in the experimental tube, in other words, they are killed. And opponents argue that the use of therapeutic cloning is wrong, regardless of whether those cells are used to benefit sick or injured people, because it is wrong to take the life of one to give it to another.
κλών - “twig, shoot, offspring”) - in the most general sense - exact reproduction of any object. Objects resulting from cloning are called a clone. And both each individually and the entire series.Human cloning- an action consisting in the formation and cultivation of fundamentally new [ specify] human beings, accurately reproducing not only externally, but also at the genetic level of one or another individual, currently existing or previously existing.
Technology
The technology for human cloning has not yet been developed. Currently, not a single case of human cloning has been reliably recorded. And here a number of both theoretical and technical questions arise. However, today there are methods that allow us to say with a high degree of confidence that the main issue of technology has been resolved.
The most successful method of cloning higher animals was the “nucleus transfer” method. It was he who was used to clone the sheep Dolly in the UK, who lived for six and a half years and left behind 6 lambs, so that we could talk about the success of the experiment. According to scientists, this technique is the best we have today to begin the actual development of human cloning techniques.
The method of parthenogenesis, in which the division and growth of an unfertilized egg is induced, looks more limited and problematic; even if it is implemented, it will only allow us to talk about success in cloning female individuals.
The so-called technology of “splitting” the embryo, although it should produce genetically identical between themselves individuals cannot ensure their identity with a “parent” organism, and therefore cloning technology in the strict sense of the word is not and is not considered as a possible option.
Approaches to human cloning
Human reproductive cloning
Human reproductive cloning - assumes that an individual born as a result of cloning receives a name, civil rights, education, upbringing, in a word - leads the same life as all “ordinary” people. Reproductive cloning faces many ethical, religious, and legal problems that today do not yet have an obvious solution. In some states, reproductive cloning work is prohibited by law.
Therapeutic human cloning
Therapeutic human cloning - assumes that the development of the embryo stops within 14 days, and the embryo itself is used as a product for obtaining stem cells. Legislators in many countries [ specify] they fear that the legalization of therapeutic cloning will lead to its transition to reproductive cloning. However, in some countries (USA, UK) therapeutic cloning is allowed.
Obstacles to cloning
Technological difficulties and limitations
The most fundamental limitation is the impossibility of repetition of consciousness, which means that we cannot talk about the complete identity of individuals, as is shown in some films, but only about conditional identity, the measure and boundaries of which are still subject to research, but identity is taken as a basis for support identical twins. The inability to achieve one hundred percent purity of experience causes some non-identity of clones, for this reason the practical value of cloning is reduced.
Social and ethical aspect
Concerns arise from such points as the high percentage of failures during cloning and the associated possibility of the emergence of defective people. As well as issues of paternity, maternity, inheritance, marriage and many others.
Ethical-religious aspect
From the point of view of the main world religions (Christianity, Islam, Judaism), human cloning is either a problematic act or an act that goes beyond the scope of doctrine and requires theologians to clearly justify one or another position of religious hierarchs.
The key point that causes the greatest rejection is the false premise that in order to obtain a clone of one person, it is supposedly necessary to kill the embryo of another human embryo, which is at a very early stage of development, but has already begun to form (in fact, the classical cloning scheme involves the use of an unfertilized egg, the nucleus of which is replaced the nucleus of a somatic cell - the embryo of another individual does not appear in the scheme; Dolly the sheep and the Kumulina mouse were obtained using this scheme).
As for cloning, as a scientific experiment, it makes sense if it benefits a specific person, but if it is used all the time, there is nothing good in it
At the same time, some non-religious movements (Raelites) actively support developments in human cloning.
Attitude in society
A number of public organizations (WTA) advocate lifting restrictions on therapeutic cloning.
Biological safety
Issues of biological safety of human cloning are discussed. Such as: long-term unpredictability of genetic changes, the danger of leakage of cloning technologies to criminal and/or international terrorist structures.
Human cloning legislation
1996-2001
The only international instrument that prohibits human cloning is the Additional Protocol to the Convention for the Protection of Human Rights and Human Dignity in relation to the Applications of Biology and Medicine, relating to the prohibition of the cloning of human beings, which was signed on January 12, 1998 by 24 countries out of 43 member countries of the Council. Europe (the Convention itself was adopted by the Committee of Ministers of the Council of Europe on April 4, 1997). On March 1, 2001, after ratification by 5 countries, this Protocol entered into force.
2005
On February 19, 2005, the United Nations called on UN member states to pass legislation banning all forms of cloning as they are “contrary to human dignity” and are against the “protection of human life.” The UN Declaration on Human Cloning, adopted by General Assembly resolution 59/280 on 8 March 2005, calls on Member States to prohibit all forms of human cloning to the extent that they are incompatible with human dignity and the protection of human life.
During the discussion at the UN level, several options for a declaration were considered: Belgium, Britain, Japan, South Korea, Russia and a number of other countries proposed leaving the issue of therapeutic cloning to the discretion of the states themselves; Costa Rica, the USA, Spain and a number of others have advocated a complete ban on all forms of cloning.
Criminal liability
Currently, the process of criminalizing human cloning is actively unfolding in the world. In particular, such compounds are included in the new criminal codes of Spain 1995, El Salvador 1997, Colombia 2000, Estonia 2001, Mexico (Federal District) 2002, Moldova 2002, Romania 2004). In Slovenia, a corresponding amendment to the Criminal Code was made in 2002, in Slovakia - in 2003.
In France, amendments to the Criminal Code providing for liability for cloning were made in accordance with the Bioethics Law of August 6, 2004.
In some countries (Brazil, Germany, Great Britain, Japan) criminal liability for cloning is established by special laws. For example, the German Federal Embryo Protection Act of 1990 makes it a crime to create an embryo that is genetically identical to another embryo derived from a living or dead person.
In the UK, the relevant criminal provisions are contained in the Human Reproductive Cloning Act 2001, which provides for a sanction of 10 years' imprisonment. However, therapeutic human cloning is permitted.
In the United States, a ban on cloning was first introduced back in 1980. In 2003, the US House of Representatives passed a law (Human Cloning Prohibition Act of 2003), according to which cloning aimed at both reproduction and medical research and treatment is considered as a felony with a possible 10-year prison sentence and a $1 million fine. In January 2009, the ban on therapeutic cloning was lifted.
In Japan, on November 29, 2000, the Diet passed the “Law Regulating the Use of Human Cloning Technology and Other Similar Technologies,” which contains criminal sanctions.
Human cloning in Russia
Although Russia does not participate in the above-mentioned Convention and Protocol, it has not remained aloof from global trends, having responded to the challenge of the time by adopting the Federal Law “On a temporary ban on human cloning” dated May 20, 2002 No. 54-FZ.
As stated in its preamble, the law introduced a temporary (for a period of five years) ban on human cloning, based on the principles of respect for people, recognition of the value of the individual, the need to protect human rights and freedoms, and taking into account the insufficiently studied biological and social consequences of human cloning. Taking into account the prospects for using existing and developing technologies for cloning organisms, it is possible to extend the ban on human cloning or to lift it as scientific knowledge in this area accumulates and moral, social and ethical standards are determined when using human cloning technologies.
The Act defines human cloning as “the creation of a human being who is genetically identical to another living or deceased human being by transferring the nucleus of a human somatic cell into an enucleated female reproductive cell,” meaning that we are talking only about reproductive cloning, not therapeutic cloning.
According to Art. 4 of the Law, persons guilty of violating it are liable in accordance with the legislation of the Russian Federation.
The law expired in June 2007, and for the next two years the issue of human cloning was not regulated in any way by Russian laws. However, at the end of March 2010, the ban on human cloning in Russia was extended.
The new bill amends the federal law “On a temporary ban on human cloning” to extend the moratorium on cloning for an indefinite period - until the law establishing the procedure for the use of biotechnologies in this area comes into force.
The reason for the ban is stated in the explanatory note to the bill: “Human cloning faces many legal, ethical and religious problems that currently have no obvious solution.”
The new law stipulates that cloning of other organisms, as well as any cells, including human ones, for research purposes is not prohibited.
Some politicians have expressed regret over the extension of the ban on human cloning. In particular, State Duma deputy Vladimir Zhirinovsky said:
We will definitely strive to lift the ban on human cloning - this is necessary for the economy, for demography, for the family, for traditions, this is only beneficial, there is no harm here.
Identity of clones
Contrary to popular misconception, a clone, as a rule, is not a complete copy of the original, since during cloning only the genotype is copied, but the phenotype is not copied.
Moreover, even if they develop under the same conditions, cloned organisms will not be completely identical, since there are random deviations in development. This is proven by the example of natural human clones - monozygotic twins, which usually develop under very similar conditions. Parents and friends can tell them apart by the location of their moles, slight differences in facial features, voice and other characteristics. They do not have identical branching of blood vessels, and their papillary lines are also far from completely identical. Although the concordance of many traits (including those related to intelligence and character traits) in monozygotic twins is usually much higher than in dizygotic twins, it is not always one hundred percent.
Human cloning in popular culture
In science fiction, many authors have written about cloning. Nancy Friedman's novel Joshua, Nobody's Son is about the cloning of an assassinated American president (with the hint that this is John Fitzgerald Kennedy). In Ira Levin's novel "Boys from Brazil" (and in the film based on this novel), Adolf Hitler is cloned, in Anatoly Kudryavitsky's story "Parade of Mirrors and Reflections" - Yuri Andropov. In the children's detective story "The House of the Scorpion", written by Nancy Farmer, tells the story of the life of a clone boy created by a Mexican drug lord. Films from the Star Wars series, Battlestar Galactica, “The Sixth Day”, “The Fifth Element”, “Resident Evil 4: Afterlife”, “Never Let Me Go (film)”, “The Island”, “Another” are devoted to the same topic. "Moon 2112", Brazilian TV series "Clone". The protagonist of the game Hitman is a clone.
see also
Notes
- AAAS Policy Brief: Human Cloning USA: “As of 2006, fifteen states had laws dealing with human cloning. All either prohibited reproductive cloning entirely or prohibit the use of government funding for reproductive cloning.", "Many nations, including the UK, China, and South Africa, have explicitly prohibited reproductive cloning while allowing research cloning."
- Database on cloning bans in different countries - Global Lawyers and Physicians
Recently, there has been active debate in political, scientific circles and in the media about the two types of cloning: therapeutic and reproductive, as well as about the so-called “stem cells” and their significance for the further development of modern medicine.
What does all this mean from a specialist’s point of view?
Reproductive cloning
This is an artificial reproduction in laboratory conditions of a genetically accurate copy of any living creature. Dolly the sheep, born at Edinburgh's Roslin Institute, is an example of the first such cloning of a large animal.
The process is divided into several stages. First, an egg is taken from a female individual, and the nucleus is extracted from it using a microscopic pipette. Then any cell containing the DNA of the cloned organism is injected into the anucleated egg. In fact, it mimics the role of sperm in fertilizing an egg. From the moment the cell merges with the egg, the process of cell reproduction and embryo growth begins (Scheme 1).
In many countries around the world, including the UK, human reproductive cloning for the purpose of producing cloned children is prohibited by law.
Therapeutic cloning
This is the same reproductive cloning, but with the embryo growth period limited to 14 days, or, as experts say, a “blastocyst.” After two weeks, the process of cell reproduction is interrupted.
According to most scientists, after 14 days, the central nervous system begins to develop in embryonic cells and the conglomerate of cells (embryo, blastocyst) should already be considered a living being.
Such cloning is called therapeutic only because the embryonic cells formed during the first 14 days are capable of subsequently turning into specific tissue cells of individual organs: heart, kidneys, liver, pancreas, etc. - and used in medicine for the treatment of many diseases.
Such cells of future organs are called “embryonic stem cells.”
In the UK, scientists are allowed to use therapeutic cloning and conduct research on stem cells for medical purposes.
In Russia, many scientists (for example, Academician of the Russian Academy of Medical Sciences N.P. Bochkov, Professor V.Z. Tarantul from the Institute of Molecular Genetics) do not like to use the expression “therapeutic cloning” and prefer to call this process “cellular reproduction.”
Embryonic stem cells
They are formed in the embryo (blastocyst) in the first days of reproduction. These are the ancestors of the cells of almost all tissues and organs of an adult.
They have been known to embryologists for a long time, but in the past, due to the lack of biotechnology for their laboratory cultivation and preservation, such cells were destroyed (for example, in abortion clinics).
Over the past decades, not only the biotechnology of artificially obtaining embryonic stem cells by cloning has been developed, but also special nutrient media have been created for growing living tissues from them.
Future medicine - medicine of "spare parts"
The development of many areas of medicine in the next century will be based on the use of embryonic stem cells.
That is why today in scientific and political circles so much attention is paid to the issues of therapeutic cloning and stem cell research for medical purposes.
What are the practical benefits?
The development of biotechnology for obtaining large quantities of stem cells will enable doctors to treat many still incurable diseases. First of all - diabetes (insulin dependent), Parkinson's disease, Alzheimer's disease (senile dementia), heart muscle diseases (myocardial infarction), kidney disease, liver disease, bone disease, blood disease and others.
New medicine will be based on two main processes: growing healthy tissue from stem cells and transplanting such tissue to the site of damaged or diseased tissue.
The method of creating healthy tissues is based on two complex biological processes: the initial cloning of human embryos to the stage of the appearance of “stem” cells and the subsequent cultivation of such cells and the cultivation of the necessary tissues and, possibly, organs in nutrient media.
Professor Vyacheslav Tarantul from the Moscow Institute of Molecular Genetics of the Russian Academy of Sciences even proposes, from the moment of birth of any child, to create a bank of stem cells for each child from embryonic cells (for example, his own umbilical cord). In 40-50 years, if any organs or tissues become diseased or damaged, it will always be possible to grow from this bank a replacement for the damaged tissue, which will be genetically completely identical to this person. In this case, no foreign donor organs or transplants are needed (Scheme 2).
What is the danger?
If the process of reproduction of cells obtained as a result of cloning (including for therapeutic purposes) does not stop at the 14-day limit, and the embryo is placed in the woman’s uterus, then such an embryo will turn into a fetus and subsequently into a child. Thus, under certain conditions, “therapeutic” cloning can turn into “reproductive” cloning.
Some specialists are already trying to use cloning biotechnology, for example, to treat infertility in childless families by creating child clones of infertile parents (Italian professor Severino Antinori, American professor Panos Zavos and others).
In the UK, reproductive cloning of children is punishable by up to 10 years in prison.
