What is cloning?

The following is more knowledge about cloning

Clone is the transliteration of English clone. Simply put, it is an artificially induced asexual reproduction method. But cloning is different from asexual reproduction. Asexual reproduction refers to a reproductive method in which only one organism produces offspring without the combination of male and female reproductive cells. Common ones include sporulation, budding and fission. The production of new individuals from the roots, stems, leaves, etc. of plants through layering, cutting or grafting is also called asexual reproduction. Animals such as sheep, monkeys and cattle cannot reproduce asexually without artificial manipulation. Scientists call the reproduction process of artificial genetic manipulation of animals and plants cloning, and this biotechnology is called cloning technology.

The idea of ​​cloning technology was first proposed by German embryologists in 1938. In 1952, scientists first used frogs to conduct cloning experiments. Since then, people have continued to use various animals to conduct cloning technology research. Research reached a low point in the early 1980s as the technology made little progress. Later, some people succeeded in cloning using mammalian embryonic cells. On July 5, 1996, British scientist Dr. Ian Wilmut cloned a live-born sheep using adult sheep somatic cells, which brought a major breakthrough to the research on cloning technology. It broke through the previous method of using embryonic cells to clone animals. Despite the technical difficulties of cloning, the goal of animal cloning using somatic cells was achieved for the first time, achieving animal replication in a higher sense. The goal of research into cloning is to find better ways to alter the genetic makeup of livestock, creating herds of animals that can provide better food or any chemicals consumers may need.

The basic process of cloning is to first transplant the nucleus of a donor cell containing genetic material into an egg cell with the nucleus removed, then use microcurrent stimulation to fuse the two into one, and then promote the new cell. Split reproduction develops into embryos. When the embryos develop to a certain level (the time used by Roslin Institute to clone sheep is about 6 days), they are implanted into the uterus of animals to make the animals pregnant so that they can give birth to animals that are genetically identical to the person who provided the cells. . If the donor cells are genetically modified during this process, the same changes will occur in the genes of the offspring of asexually reproduced animals. The main difference between the "Honolulu technology" that has successfully cultivated three generations of cloned mice and the technology of cloning Dolly the sheep is that the genetic material in the cloning process is not cultured in culture medium, but directly injected into the egg cells through physical methods. In this process, chemical stimulation is used instead of electrical stimulation to regain control of the egg cells. On July 5, 1998, scientists from Japan's Ishikawa Prefecture Livestock Comprehensive Center and the Kinki University Livestock Research Laboratory announced the birth of two calves cloned from adult animal somatic cells. The birth of these two cloned cows shows that the technology for cloning adult animals is reproducible.

When Scotland's Roslin Institute used cloning technology to clone Dolly the sheep in 1996, the result was immediately hailed as one of the most significant and controversial technological breakthroughs of this century. The benefits of this breakthrough are obvious. This technology can be used to rescue rare and endangered animals, replicate excellent livestock individuals, expand the population of well-bred animals, improve the genetic quality and production performance of the herd, provide sufficient experimental animals, promote research on genetically modified animals, overcome genetic diseases, and develop high-level new drugs. , and play a role in research on producing internal organs for human transplantation.

While affirming the positive effects of this technology, people have expressed concerns about this technology to a greater extent. If this asexual reproduction technology is widely promoted in the animal husbandry, it is likely to destroy the ecological balance and lead to the large-scale spread of some diseases; if it is used Applying it to human reproduction will create a huge ethical crisis.

After the identity of the cloned sheep Dolly was revealed, scientists in Oregon, USA, also confirmed that they had used cloned embryos to create monkeys in August 1996; there were also rumors that a Belgian doctor had accidentally cloned a boy. .

Although Belgian scientists deny reports of human cloning, governments of various countries attach great importance to the possible legal and ethical impacts of cloning technology. The United States, Germany, France, the United Kingdom, Canada and other countries have established expert groups to study this issue, and scientists have also Requests that research in this area be restricted. Hiroshi Nakajima, Director-General of the World Health Organization, and the European Commission member responsible for scientific research issued separate statements and remarks on March 11, 1997, expressing their opposition to human cloning experiments. At present, the consensus among various countries on this technology is to formulate laws to strengthen the management of this technology and strictly prohibit the use of it to copy humans. Wilmut, the British scientist who cloned Dolly the sheep, also said that the technology used to clone Dolly was extremely inefficient and had led to the birth of animals with congenital defects before he successfully cloned Dolly. Using this technology on humans would be "very inhumane".

The Chinese government also attaches great importance to cloning technology and the related issues it raises. The National Science and Technology Commission, the Ministry of Agriculture and other departments have held many seminars and symposiums with the participation of experts from various fields, and reached an agreement on relevant issues* **knowledge. Experts believe that the success of animal cloning technology is a major event in scientific research. It has both beneficial and disadvantageous aspects. Measures must be taken to regulate and strictly control the harmful aspects so that this technology can benefit people. human beings.

On November 11, 1997, the 29th General Conference of UNESCO adopted a document entitled "Universal Declaration on the Human Genome and Human Rights" in Paris, clearly opposing the use of cloning technology to reproduce humans. The document points out that the results of biology, genetics and medicine in human genome research should be used, but this research must be for the purpose of maintaining and improving public health and practices that are contrary to human dignity, such as using cloning technology to reproduce humans. This practice is not allowed.

On January 12, 1998, 19 European countries signed a European protocol on banning human cloning in Paris, France. This is the first international legal document prohibiting human cloning and is a supplement to the European Biomedical Treaty. This ban on human cloning stipulates that research institutions or individuals in the signatory countries are prohibited from using any technology to create people who are genetically similar to a living or dead person, otherwise they will be severely punished. Researchers and doctors who violate the agreement will be prohibited from engaging in research and practicing medicine, and the license of the relevant institute or hospital will be revoked. Legal liability will also be pursued if research institutions or individuals in signatory countries conduct such activities outside Europe. The countries that signed the agreement are France, Denmark, Lithuania, Finland, Greece, Ireland, Italy, Latvia, Luxembourg, Moldova, Norway, Portugal, Romania, Slovenia, Spain, Sweden, Macedonia, Turkey and San Marino.

The development of cloning technology

Clone is the transliteration of Clone, which means asexual reproduction, and cloning technology is asexual reproduction technology. The recently reported success of the cloned sheep Dolly from the Roslin Institute in the UK was the first successful cloning using somatic cells. It opened a new page in the history of bioengineering.

Cloning technology has gone through three stages of development:

The first stage is microbial cloning, that is, one bacterium replicates thousands of identical bacteria. into a bacterial colony.

The second period is biotechnology cloning, such as DNA cloning.

The third period is animal cloning, which is cloning one cell into an animal.

In nature, there are many plants with innate cloning instinct, such as sweet potatoes, potatoes, roses and other plants propagated by cuttings. Animal cloning technology has experienced the development process from embryonic cells to somatic cells. As early as the 1950s, American scientists used amphibians and fish as research subjects and pioneered the cell nuclear transplantation technology. They studied the potential of cell development and differentiation and the interaction between the cytoplasm and the nucleus.

In 1986, British scientist Willardson first cloned a sheep from embryonic cells using nuclear transfer. Later, others successively cloned cows, sheep, mice, rabbits, monkeys and other animals. my country has also made great achievements in cloning technology. In the late 1980s, my country cloned a rabbit. In 1991, the Development Research Institute of Northwest Agricultural University and Jiangsu Agricultural College successfully cloned sheep. In 1993, the Institute of Developmental Biology of the Chinese Academy of Sciences and the College of Agriculture of Yangzhou University** * Collaborated to clone a group of goats. In 1995, South China Normal University and Guangxi Agricultural University collaborated to clone cattle. Then the Animal Husbandry Institute of the Chinese Academy of Agricultural Sciences succeeded in cloning cattle in 1996. The United States has recently succeeded in cloning monkeys, and Japanese scientists also claim that they have bred more than 200 "cloned cows." The cloned animals mentioned above were all successfully achieved by using embryonic cells as donor cells for nuclear transplantation.

In February 1997, the Roslin Institute in the UK announced that Dolly the sheep had been successfully cloned. Mammary epithelial cells were used as donor cells for nuclear transplantation. This opened a new page in the history of biological cloning. It broke through the traditional method of using embryonic cells for nuclear transfer and made great progress in cloning technology. The entire cloning process is as follows: scientists selected three ewes, first sucked out all the genetic material from the egg cells of one ewe, and then fused the mammary gland cells of another 6-year-old ewe with them to form a new genetic material. The egg cell is then divided and developed into an embryo. When the embryo grows to a certain extent, it is implanted into the uterus of a third ewe, who then gestates and gives birth to the cloned sheep Dolly. Dolly is like the 6-year-old ewe who provided the mammary gland cells. Dolly the sheep is the first animal in the world to be successfully cloned using somatic cells. The success of cloning Dolly theoretically proves that highly differentiated cells can return to the zygotic function of the fertilized egg after being treated by certain means; it also shows that during the development process, the cytoplasm has a regulatory effect on the development of heterologous cell nuclei. It provides an important way for the treatment of biological genetic diseases, the cultivation and expansion of excellent varieties, etc. It plays a certain role in the optimization of species, the preservation of germplasm of endangered animals, and the expansion of genetically modified animals. Since the success of cloning Dolly the sheep, countries around the world have aroused strong reactions. Some regard it as a blessing, while others regard it as a disaster. The author believes that new technologies should be supported. The biggest benefit of breakthroughs in biological cloning is to cultivate a large number of qualities. Excellent livestock enrich people's material life, reduce the cost and improve the efficiency of animal husbandry, and can also provide certain pharmaceutical raw materials to improve human immune function and so on. Before Dolly the Sheep, the Roslin Institute had bred a genetically modified sheep whose milk contained drug ingredients for the treatment of hemophilia. A company bought it for a high price of 500,000 pounds. If somatic cells are used to "replicate" this sheep in large numbers, the lives of more patients can be saved. In addition, cloning technology can be used to copy a large number of rare animals, save endangered species, adjust the ecological balance of nature, and benefit mankind. Why worry? Of course, cloning technology may also have negative effects. Some cloned animals are genetically completely Wait, infection by a specific virus or other disease will bring disaster. Unplanned cloning of animals will disrupt the evolution of species and interfere with sex ratios. This artificial control of the biological world will bring many unexpected consequences. hazards. But as long as we adopt corresponding research strategies and formulate a scientific cloning plan, this negative effect can be avoided.

As for human cloning, this is a meaningless research topic. Contemporary biological history has proven that cloning technology can only copy creatures with the same appearance and characteristics, but cannot clone the original talents of the copied person. Human thinking is subject to acquired constraints. Therefore, even if someone can clone a figure who looks exactly like a great leader or great scientist in history, he or she will only be the same in appearance but lack the thoughts, temperament, and talents of a great leader or great scientist. What is the significance of such cloning? As for some people who advocate cloning humans to obtain human organs for medical transplantation, this is also not feasible. Because the cloned person is first and foremost a citizen, he enjoys human rights. If the cloned person refuses to donate his organs, you, the inventor, cannot violate human rights.

As for cloning headless people, that is also unrealistic, because in order to survive, cloned people must first eat and think. It is impossible without a head. We can't cultivate a headless vegetative person, right? And, the most important thing is Human cloning is not in line with the world's conditions and national conditions. The world's population is expanding rapidly, and many countries have implemented family planning to control population growth. Under such circumstances, how can we spend huge sums of money to do things that go against the laws of social development? As Rutte, the German Minister of Research and Technology, Gus said: "Copying human beings will not be allowed and will definitely not happen." Currently, cloning technology has made new progress in the UK. They have applied this technology to human hematopoiesis. Dr. Ross James, director of the British company PPL, which is the economic backbone of cloning technology, said: "We know from studying Dolly that we can create a genetically modified animal from one cell. We are now using this technology to produce human blood. The most important component, which is plasma." They worked with the Roslin Institute on a type of cow and sheep with human genes. They first remove the plasma from animals and then replace it with human plasma. The genetically modified cattle and sheep contain important components of human plasma. By raising, cloning or breeding these animals, they can obtain stable and reliable products. Moreover, the relatively cheap blood resource is worth up to 150 pounds per year in the UK according to statistics. It can be said to be of great benefit. The prospects of cloning technology are immeasurable.

Chronicles of cloning research

1938: German scientists first proposed the idea of ​​cloning.

1952: Scientists begin experiments with frog cloning.

1970: A breakthrough was achieved in experiments with cloning frogs. It was claimed that frog eggs developed into tadpoles but died after they began to eat.

1981: Scientists conducted experiments on cloning mice. It was said that mice with normal development were created using mouse embryonic cells.

1984: The first embryonic cloned sheep is born.

February 24, 1997: The Roslin Institute in the UK announced the successful breeding of cloned sheep. They successfully created a cloned sheep using mammary gland cells taken from a 6-year-old adult sheep.

February 23, 1998: The British company PPL Medical announced that the company had cloned a calf, Mr. Jefferson.

July 5, 1998: Japanese scientists announced the birth of two calves cloned from adult animal cells.

July 22, 1998: Scientists used a new cloning technology to successfully create more than 50 cloned mice of three generations using the somatic cells of adult mice. This was the first time that humans had used Clone animals clone clone animals.

May 31, 1999: Scientists from the University of Hawaii in the United States cloned the first male mouse using adult somatic cells.

January 3, 2000: American scientists announced the success of cloning a rhesus monkey and named it "Tetra".

January 2000: American scientists announced the success of monkey cloning, and the rhesus monkey was named "Tetra".

March 14, 2000: The British company PPL announced that they had successfully cloned five cloned pigs. This was the first time that humans had bred cloned pigs.

January 27, 2001: American and Italian scientists announced that they would join forces to try Cologne.

“Science is a double-edged sword.” Good people can use it to serve and benefit mankind, while evil people can use it to harm human existence. Since sheep and humans are both mammals, sheep cloning technology can also be used to clone other mammals, including humans. If someone uses individual cloning technology to clone humans, it will bring endless disasters to mankind. This is why government officials in many countries explicitly prohibit the use of animal cloning technology in humans.

What is the public’s opinion on human cloning? The American Broadcasting Corporation (ABC) once conducted a poll, and the results showed that: 87% of people opposed human cloning, 82% believed that human cloning was not in line with traditional human ethics, and 93% People are opposed to copying themselves, and 53% of people think it is okay if human cloning is limited to medical purposes. Therefore, we must also follow the laws of human equality and oppose the abuse of sheep cloning technology on humans. As human society continues to develop, people's ideas will continue to change. For example, in the past, many people opposed the development of in vitro fertilization, but now that in vitro fertilization has been accepted by people, it is difficult to predict what attitude people will have towards human cloning in the future. If even one day, people accept the application of sheep cloning technology to human cloning, then we should do what we do now with in vitro fertilization.

Brigitte Boisselier, head of Clonaid, said that the newly born clone has been named "Eve". Boisselier said the girl was born on Thursday but did not disclose the place of birth.

Clone" is transliterated from the English "clone" and has three different levels of meaning in the field of biology.

1. At the molecular level, cloning generally refers to DNA cloning ( Also called molecular cloning), it means inserting a specific DNA fragment into a vector (such as plasmid and virus, etc.) through recombinant DNA technology, and then replicating itself in the host cell to obtain a large number of identical DNA fragments. "Population".

2. At the cellular level, a clone is essentially a population of cells formed by the division of a single ancestral cell, e.g. A group of cells with the same genetic background formed by dividing cells in culture medium in vitro for several generations is a cell clone. For another example, in vertebrates, when foreign substances (such as bacteria or viruses) invade, it will occur. Specific recognition antibodies are produced through immune reactions. All plasma cells that produce a specific antibody are divided from one B cell. Such a plasma cell population is also a cell clone. Cell cloning is a low-level form of reproduction - asexuality. Reproduction, that is, without sexual union, the offspring and the parent have the same genetics. The lower the level of biological evolution, the more likely it is to adopt this method of reproduction.

3. At the individual level, cloning means. A group of two or more individuals with identical genotypes. For example, two identical twins are a clone! Because they come from the same egg cell, their genetic background is exactly the same. "Dolly" cannot be said to be a clone! Because "Dolly" is just a single clone. Only if those British embryologists can transplant two or more identical nuclei into two or more identical enucleated egg cells, a clone will be obtained. The word clone can only be used to describe two or more "Dolly"s with the same genetic background. Therefore, in the sensational paper published in Nature in February 1997, the author did not refer to "Dolly". Said to be a clone.

In addition, cloning can also be used as a verb, which means the process of obtaining the above-mentioned DNA, cells or individual groups.

2. Cloning technology<. /p>

1. DNA cloning

There are many methods for DNA cloning. The basic process is shown in the figure below (not to scale)

As you can see, we get DNA can be used in many aspects of biological research, including the analysis and processing of specific DNA base sequences, and the mass production of valuable proteins in the biotechnology industry.

2. Cloning

(1) Cloning of plant individuals

In the 1950s, botanists used carrots as model materials to study whether genetic material was lost in differentiated plant cells. They were surprised to find that a complete plant could develop from a single highly differentiated carrot cell! From this, they believed that plant cells are totipotent.

The genetic background of the carrot population developed from more than two somatic cells in one carrot is exactly the same, so it is a clone. Such a plant cloning process is a complete asexual reproduction process!

(2) Cloning of individual animals

① The birth of “Dolly”

1997 On February 27, Ian Wilmot's scientific research team at the Roslin Institute in Edinburgh, UK, announced to the world that the world's first cloned sheep, "Dolly", was born. This news immediately caused a sensation around the world. .

The creation of "Dolly" is related to three ewes. One is a three-month-old Finnish Dorset ewe, and the two are Scottish black-faced ewes. The Finnish Dorset ewe provided the complete set of genetic information, that is, the nucleus (called the donor); a Scottish Blackface ewe provided the egg cell without a nucleus; and another Scottish Blackface ewe provided the development of the sheep embryo. The environment - the uterus, is the "birth" mother of "Dolly" sheep. The entire cloning process is briefly described as follows:

Mammary gland cells were taken out from the mammary glands of Dorset ewe sheep in Finland and put into low-concentration nutrient culture medium. The cells gradually stopped dividing. This cell is called It is a donor cell; a Scottish black-faced ewe is injected with gonadotropin to induce ovulation, the unfertilized egg cell is taken out, and its nucleus is immediately removed, leaving a nucleus-free egg cell. This cell is called the recipient. cells; the method of electric pulse is used to fuse the donor cell and the recipient cell, and finally a fused cell is formed. Since the electric pulse can also produce a series of reactions similar to the natural fertilization process, the fused cell can also behave like a fertilized egg. The cells divide and differentiate in the same way to form embryonic cells; the embryonic cells are transferred to the uterus of another Scottish black-faced ewe, and the embryonic cells further differentiate and develop, finally forming a lamb. Dolly lambs are born with the exact same appearance as Dorset ewes.

A year later, another group of scientists reported that more than 20 cells were obtained by transplanting the nuclei of mouse cumulus cells (highly differentiated cells surrounding the periphery of oocytes) into oocytes with their nuclei removed. Only fully developed mice. If there is only one "Dolly" and it is not enough to be called a cloned sheep, these mice are truly cloned mice.

② The basic process of cloning mice through nuclear transfer

In this experiment, cumulus cells were obtained through the following process: through several consecutive injections of chorionic gonadotropin, Inducing female mice into a state of high egg production. Complexes of cumulus cells and oocytes were then collected from the oviducts of female mice. Cumulus cells were dispersed by hyaluronic acid treatment. Select cumulus cells with a diameter of 10-12 microns as the nucleus donor (previous experiments have shown that if the nuclei of cumulus cells with smaller or larger diameters are used, the oocytes that have undergone nuclear transplantation will rarely develop to the 8-cell stage. ). The selected cumulus cells were kept in a certain solution environment and the nuclei were transplanted within 3 hours (different from this, the breast cells used as nucleus donors when obtaining "Dolly" were first passaged in the culture medium for 3 hours. -6 times)

Oocytes (generally in meiotic metaphase II) were collected from female mice of different species by methods similar to those described above. Carefully remove the nucleus of the oocyte using a thin tube with a diameter of approximately 7 microns under a microscope, and try not to remove the cytoplasm. Also carefully remove the nucleus of the cumulus cells and remove as much cytoplasm as possible (by moving the removed nucleus back and forth several times in the glass tube to remove a small amount of cytoplasm). Inject directly into the oocyte from which the nucleus has been removed within 5 minutes after the nucleus is removed. The oocytes that have undergone nuclear transfer are first placed in a special solution for 1-6 hours, and then divalent strontium ions (Sr2) and cytostatin B are added. The former activates the oocyte, and the latter inhibits the formation of polar bodies and the elimination of chromosomes. The treated oocytes are then taken out and placed in a special solution without strontium and cytostatin B to cause cell division to form embryos.

Embryos of different stages (from the 2-cell stage to the blastocyst stage) were implanted into the fallopian tubes or uterus of pseudopregnant female mice that had been mated with ligated male mice a few days ago. Fully developed fetal mice are surgically removed after approximately 19 days.

At present, animals cloned by embryonic cell nuclear transfer include mice, rabbits, goats, sheep, pigs, cows and monkeys. In China, in addition to monkeys, other animals are cloned, and goats can also be cloned by continuous nuclear transfer. This technology goes further than embryo segmentation technology and will clone more animals. Because the more times the embryo is divided, the fewer cells each share, and the worse the ability of the individual to develop. There is only one animal cloned by somatic cell nuclear transfer, and that is Dolly the sheep.

3. The gospel of cloning technology

1. Cloning technology and genetic breeding

In agriculture, people have used "cloning" technology to cultivate a large number of high-quality, high-yielding varieties that are resistant to drought, lodging, and pests and diseases, which has greatly increased grain yields. In this regard, our country has entered the forefront of the world's most advanced countries.

2． Cloning technology and the protection of endangered organisms

Cloning technology is a boon to the protection of species, especially rare and endangered species, and has great application prospects. From a biological perspective, this is also one of the most valuable aspects of cloning technology.

3. Cloning Technology and Medicine

In modern times, doctors can perform transplant operations on almost all human organs and tissues. But in terms of science and technology, rejection in organ transplantation is still the most troublesome thing. The reason for rejection is poor tissue compatibility due to tissue mismatch. If the organs of a "cloned human" are provided to an "original human" for organ transplantation, there will be absolutely no worries about rejection, because the genes and tissues of the two are matched. The question is, is it humane to use "human clones" as organ donors? Is it legal? Does it make financial sense?

Cloning technology can also be used to reproduce valuable genes in large quantities. For example, in medicine, people use "cloning" technology to produce insulin to treat diabetes and growth hormone to make patients with dwarfism grow taller again. And streptozolin, which can resist various viral infections, etc.

Answer: Zero posts - Assistant Level 2 3-12 18:52

What is cloning

Clone is the transliteration of the English word clone, clone Derived from the Greek word klon, the original meaning refers to seedlings or twigs. Plants are cultivated through vegetative or vegetative propagation, such as stem cutting and grafting.

Today, cloning refers to the asexual reproduction of organisms through somatic cells, and a population composed of offspring individuals with identical genotypes formed by asexual reproduction. Cloning can also be understood as copying, which is to produce the same copy from the prototype. Its appearance and genetics are exactly the same as the prototype.

In February 1997, news of the birth of "Dolly" the sheep was revealed, which immediately attracted worldwide attention. This cloned sheep was bred by British biologists through cloning technology, which meant that humans could use animals to A single somatic cell produced a life form that was exactly the same as this animal, breaking the eternal laws of nature.

How to evaluate cloning technology?

No matter how "Leillian" tries to quibble and beautify his actions, many famous scientists in the world have very similar views: "Leillian" conducts human cloning experiments without any scientific purpose. In a word, it is not for science. progress.

Many scientists believe that when commenting on the human cloning incident, it is important to first clarify: Do humans need human cloning?

Professor Ali Asanov from the Department of Genetics of Sechenov Medical College in Moscow commented that the possibilities in technology and technology greatly exceed our understanding of "what humans need".

The argument for supporters of human cloning is that the technology can help infertile people have their own offspring.

In fact, this requirement can be met through other safer and more effective ways. Therefore, it can be concluded that using cloning technology to carry on the family line is just an excuse, and there are unscientific commercial purposes hidden behind human cloning experiments.

Professor Asanov believes that at present, human cloning has no prospects and no meaning. It is worth pointing out that no one can predict the consequences of human cloning, so it is unethical to conduct human cloning experiments now.

Repairing diseased organs is the future of cloning

Professor Asanov said that the Russian scientific community firmly believes that the future of cloning technology should be the application in internal medicine therapy, that is, "internal medicine therapy" clone". The problem, however, is that the term is still extremely inaccurate.

Essentially, "medical therapy cloning" is a method of establishing cell material for transplantation. It is no different in meaning from cloning as it is now referred to. It is a method that can cultivate healthy organs. Cell technology can partially or completely replace diseased organs.

According to Professor Asanov’s explanation, scientists have just scratched the surface of the internal processes that occur in the human body. Scientists recently decoded the human genetic map, but have not yet been able to apply the knowledge gained to uncover the mysteries of the human body. To this end, scientists will have to conduct in-depth research for several years before they can perfect and master cloning technology.

Ninety-nine percent of current clones will be ugly

Professor Asanov said that Russian scientists have warned more than once that 99% of the products obtained from cloning experiments are Ugly.

Their example is: the famous cloned sheep Dolly was obtained after 300 attempts of failure. Unfortunately, Dolly was not a healthy lamb. He suffered from arthritis and other diseases and showed signs of premature aging. Additionally, various developmental malformations have been found in all other cloned animals. Russian scientists, including Professor Asanov, believe that conducting human cloning experiments under such circumstances is at least an extremely irresponsible approach. The life of a clone will be a nightmare, and by the time they are 30 years old, they will become old people.

What can be cloned

Everything that is alive can be cloned

What has been cloned now

Frog: 1962, not yet Success

Carp: As early as 1963, Chinese scientist Tong Dizhou successfully cloned a female carp by inserting the DNA of a male carp into an egg from a female carp, earlier than the cloning of Dolly the sheep. for 33 years. However, because the relevant paper was published in a Chinese scientific journal and was not translated into English, it was not known internationally. (Source: PBS)

Sheep: 1996, Dolly

Macaque: January 2000, Tetra, female

Pig: 2000 March, 5 Scottish PPL piglets; August, Xena, female

Cattle: 2001, Alpha and Beta, male

Cats: Late 2001, CopyCat (CC), Female

Mouse: 2002

Rabbit: March-April 2003, independently in France and North Korea;

Mule: May 2003 , Idaho Gem, male; June, Utah Pioneer, male

Deer: 2003, Dewey

Horse: 2003, Prometea, female

Dog: 2005, Seoul National University Experimental Team, South Korea, Snoopy

Despite great progress in cloning research, the current success rate of cloning is still quite low: researchers experienced 276 failures before Dolly was born attempts; the birth of 70 calves was successful after 9,000 attempts, and one-third of them died in infancy; Prometea also took 328 attempts to be successfully born. For some species, such as cats and orangutans, there have been no reports of successful cloning. The dog cloning experiment was also the result of hundreds of repeated tests.

A post-birth age test showed that Dolly was old at birth.

When she was 6 years old, she contracted arthritis that is common in old age. Such aging is thought to be caused by the wear and tear of telomeres. Telomeres are at the ends of chromosomes. As cells divide, telomeres wear away during replication, which is often thought to be a cause of aging. However, researchers