Abstract
Cloning is the process of creating a copy of particular organisms, including genes, tissues, and cells. There are three types of cloning, which are gene, reproductive and therapeutic ones. Although its beneficial effect is undeniable, for instance, providing an opportunity to have children for ones, who have specific illnesses, its negative impact should be taken into consideration too. Cloning causes multiple discussions on the ethics topic, as it violates human dignity. In addition, it is highlighted that the cloned organism tend to have serious problems preventing them from surviving, and premature aging is among them. This way, this issue requires further explorations and setting additional experiments.
Introduction
Cloning is considered to be one of the main achievements in the science field. It implies a technique, which is applied for creating an exact copy of an animal or human, including genes, tissues, and cells. Surprisingly, some clones already exist in nature, for instance, single-celled organisms reproduce the copies of themselves (Cloning, n.d.). As for the human world, twins appear to be almost identical. The history of this technique begins with a sheep Dolly, which was reproduced by a cell of an adult sheep. Nowadays, scientists have set up this experiment with cows, rabbits, deer, horses, and other animals, and their attempts have been fruitful. However, there is no successful copy of human in the present-day developments. In addition, the fact that clones do not present a viable organism, and there is a likelihood of genetic mistakes causing sudden death, raises some ethical concerns. This way, the purpose of this paper is to analyze the benefits of cloning and its effect on humans and animals, describe the process, and present reflections of the banning proposals.
The Process of Cloning
As has been mentioned above, cloning is currently applied only to animals. There are three types of cloning, which are gene, reproductive and therapeutic cloning. The term ‘reproductive cloning’ involves the process of somatic cell nuclear transfer (Cibeli & Gurdon, 2018). The process is depicted in detail in Scheme 1. An adult monkey, which DNA from the cell is taken, is named ‘donor’. Its DNA is removed and inserted in the egg cell of another animal. It is worthy of note that this process is applied for animals of similar kinds. The nucleus of the egg cell is erased in order to read and copy the donor’s DNA. As a result, an embryo is created and zapped with electricity in order to stimulate it to multiply. After that, the embryo transforms into a blastocyst, which is born by a surrogate mother. This way, the birth of an identical replica of the adult monkey is the final stage of the experiment.
Gene cloning implies producing a copy on the molecular level. This type implies experimental methods on the formation of recombinant DNA molecules (Oda et al., 2000). Therapeutic cloning includes creating a copy of an embryo for the aim of producing embryonic stem cells of the donor’s DNA. Such explorations contribute to understanding disease and its progression, which is helpful for elaborating new treatment methods. Tissue, which is created during five days after the start of egg dividing, appears to be the main source of embryonic stem cells. At this stage, when the cell is developing, it is called a blastocyst, the embryo contains a cluster.
Genetic Issues
Cloning is not perfect and sufficient technique, as it is a common sight when embryos are not capable of becoming healthy and viable adult organisms. As for Dolly’s case, her birth was successful after 277 attempts (Smith et al., 2000). This way, cloning is characterized by an extremely low level of efficiency. In addition, safety concerns arise around this issue too, and slow the progress significantly.
Effect on Animals
There is evidence of the negative influence of the health condition of mammal, which has been cloned, for instance, increased birth size and various defects in the organs. Scientists noticed the inappropriate functioning of the liver, brain, and heart in the cloned organisms, and these organs are crucial for a living (Greely, 1999). Furthermore, clones are susceptible to premature aging and serious problems with the immune system.
Another problem regards the relative age of cloned organisms and their cell’s chromosomes. As the cell is dividing, telomeres, which are tips of chromosomes, is shrinking too. This way, Telemachus becomes so short that the cell is not capable of diving and dies. Therefore, the donor’s chromosomes are relatively short, which significantly impacts on the life span (Ayala, 2015). Clones are highly likely to age more rapidly than normal animals.
Possible Benefits
Despite all the drawbacks, the development of cloning may supply a promising future. One of the possible applications involves the recovery of endangered species. Smith et al. (2000) highlight some experiments, which were aimed to preserve the last surviving cow of Enderby Island. In this case, cloning prevented the species from extinction, as female clones could significantly contribute to the breed recovering gradually via sex reproduction. However, it is worthy of note that this approach can be effective in case a wide pool of founder animals is involved in order to avoid probably hardships with inbreeding and genetics.
Cross-species cloning appears to be another solution for recovering endangered species. This approach implies using the nucleus of an endangered animal with a host oocyte, which belongs to a closely related and or numerous domesticated species. Although the experiments have not been successful in the majority of trials, this method is considered to be perspective in the long-term. It obtains special importance in present-day developments when ecological issues are pressing and require an innovative solution.
Furthermore, the cloned animals may be beneficial for artificial selection. The U.S. Food and Drug Administration (FDA) has confirmed that the meat and milk produced by the cloned animals are appropriate for eating (Cloning Fact Sheet, n. d.; Trounson & Pera, 1998). This occasion is extremely meaningful in order to realize intended agricultural traits, for instance, high milk production. However, the cloning process requires considerable funding, and for this reason, this opportunity will become available only in many years.
As for therapeutic cloning, it supplies some beneficial options too. Scientists highlight the unique ability of embryonic stem cells to produce all types of cells. In addition, it presents a sufficient approach for recovering injured or diseased tissues. Therefore, it supplies an excellent opportunity of molecular causes of disease exploration. Moreover, it appears to be an appropriate tool for testing new medicine. This way, cloning is highly likely to contribute to medicine development in the long term.
The Reasons for Banning and Permission
Gene cloning present a scientific filed, which is constantly developing, that is why it is elaborated in the laboratories worldwide. Reproductive and therapeutic cloning raise a considerable number of ethical issues, especially in case the appliance of its technique to human. Reproductive cloning is intended to create identical people, who were alive or now exist. This fact may lead to contradictions with religious beliefs and social values, and it interferes with human dignity, freedom, and identity. Moreover, cloning presents a satisfactory solution for couples with reproductive illnesses and realize their dream of having children. Some people also express the opinion that it may be useful for avoiding inheriting a deleterious gene. Therapeutic cloning may supply the potential for curing patients with particular illnesses or injuries. However, it requires the destruction of human embryos in the test tube.
Although human cloning does not exist now, its experiments raise a significant number of ethical concerns. The majority of countries have adopted legislation regarding human cloning. Among them are Australia, Austria, Argentina, Belgium, Brazil, Canada, the Czech Republic, Costa Rica, Denmark, France, Germany, and others. In general, approximately 46 countries are opposed this such experiments (Fiester, 2005). This way, the development of human cloning encounters significant ordeals, which slows the further exploration and scientific progress.
Conclusion
In summary, cloning presents a controversial question, and multiple opinions are expressed on this topic. Its significance for the scientific progress should not be underestimated. It provides a broad field for further explorations and has become an acceptable solution in some cases, especially for people who cannot have children. Cloning is highly likely to benefit endangered species and prevent them from total extinction. It can also be applied for artificial selection purposes. Milk and meat produced by the cloned animals do not differ from the ones, which is supplied by the normal ones. However, this process raises a considerable number of ethical concerns. For instance, it has been stated that the cloned embryos are not capable of developing into a healthy organism. They are also especially susceptible to premature aging. These facts stimulated the majority of countries to pass appropriate legislation.
References
Ayala, F. J. (2015). Genetic therapy and cloning. Proceedings of the National Academy of Sciences, 112 (29), 8879-8886.
Cibeli, J. B., & Gurdon J. B. (2018). Custom-made oocytes to clone non-human primates. Cell, 172(4), 647-649. Web.
Cloning. (n.d.). Web.
Cloning Fact Sheet. (n. d.). Web.
Fiester, A. (2005). Ethical issues in animal cloning. Perspectives in Biology and Medicine 48(3), 328-343.
Greely, H. T. (1999). Banning human cloning: A study in the difficulties of defining science. Southern California Interdisciplinary Law Journal, 131.
Liu, Z., Cai, Y., Wang, Y., Nie, Y., Zhang, C., … Sun, Q. (2018). Cloning of macaque monkeys by somatic cell nuclear transfer. Cell, 172(4), 881-887. Web.
Oda, T., Morikawa, N., Saito, Y., Masuho, Y., & Matsumoto, Y. (2000). Molecular Cloning and Characterization of a Novel Type of Histamine Receptor Preferentially Expressed in Leukocytes. Journal of Biological Chemistry, 275, 36781-3678.
Smith, L. C., Bordignon, V., Babkine, M., Fecteau, G., & Keefer, C. (2000). Benefits and problems with cloning animals. The Canadian veterinary journal = La revue veterinaire canadienne, 41(12), 919–924.
Trounson, A., & Pera, M. (1998). Potential benefits of cell cloning for human medicine. Reproduction, Fertility and Development, 10(1), 121–125. Web.