Cloning has been a particularly intriguing experiment over the years, involving acutely essential milestones and crucial researches. Many hypotheses have been generated; some accepted and others refuted. On 5 July 1996, a domestic ewe, Dolly was born by lan Wilmut and his colleagues. Dolly was the first animal to be cloned from an adult somatic cell (McLaren, 1775). Initially, people, inclusive of scientist, did not believe that somatic cell from an adult individual, could be used to generate a new individual through cloning. However, with the emergence of Dolly, the ideology was disapproved, and, it was with clear conscious that genes could be manipulated, amounting to genetically formed organisms. Dolly’s birth had a vast influence analogous to the influence generated by the discovery of DNA, the first surgery of heart transplantation and the first atomic bomb test, which took the whole world by storm. It cannot be denied that Dolly has been the world’s most famous sheep. Cloning is a sophisticated procedure, and it has created mixed reaction, attributed to some of its failure and consequent deviation from social ethics.
The pioneering technique used in cloning Dolly was somatic cell nuclear transfer. Under the leadership of lan Wilmut, nucleus cell from an adult mammary gland cell of a Finn Dorsett ewe was transplanted to an unfertilized enucleated oocyte of a Scottish blackface ewe. In tandem to this, they used electricity, which had various functions: fusing mammary gland nucleus and enucleated oocyte, becoming hybrid cell and stimulate cell division. Further, when the hybrid cell developed into a blastocyst, it was implanted in the blackface ewe, and the aftermath of the experiment was the egression of Dolly. The sheep resembled the Finn Dorsett ewe; hence it was genetically identical to the Finn Dorsett’s mammary gland nucleus and not to the Scottish blackface’s enucleated oocyte. Dolly also displayed a plethora of traits; for instance, the sheep gave birth to six lambs through sexual reproduction, clearly affirming that Dolly was fertile and had the capacity to reproduce offspring. Dolly succumbed to a progressive lung disease and severe arthritis, at the age of six.
Dolly’s birth and death are raised a new concern about the technology and wisdom of cloning, and with its success, the world of science took a new direction, and scientists began cloning other animals; cows, rats, cats and monkeys. However, the technology of animal cloning was unstable, and it experienced miscellanea obstacles, which included reduced survival rates, prediction of physiological changes, and facets related to ethical issues. In addition to this, the technology, consisting of vital body cloning had inestimable impacts, the core problem being the application and management of technology.
The survival rate of the cloning embryo is low with fewer than 4% of embryos based on the current cloning technology (Paterson, DeSousa, Ritchie, King and Wilmut, 142). Cloned animals can suffer some deadly health problems. Normally, the cloned cell results in death of the mother carrying the cloned cell. During the experiment, of cloning Dolly, lan Wilmut and his colleague used 277 hybrid cells to create 29 blastocyst; however, the result of the cloning sheep was only based on Dolly’s survival (Utah University, n. p.). Under the same light, there were many studies carried out corroborating to the proof of lower survival rate of cloned organism. According to Hill, Winger, Long, Looney, Thompson, and Westhusin, 322 hybrid cells were used to create 26 blastocyst, which were implanted. Six fetuses survived during pregnancy, but after 290 days, only one calf survived. (1137). Moreover, cloning of animals could amount to high rates of failure, attributed to several reasons; the compatibility of transferred nucleus and the enucleated egg, failure of hybrid cell to differentiate and develop properly (Wells, 252). Similarly, failure to implant embryo into a surrogate mother may result to the failure of the pregnancy itself (Wells, 253).
Cloned animals normally suffer aging problem, depicted by Dolly who died at a tender age of six years, which was quite low, when compared to the normal life expectancy of a sheep, which is 11-12 years (Stobart and Mestel, 1). The death of dolly triggered key questions about the actual age of Dolly’s cells, and to affirm this, a research was carried out in 1999; the scientists concentrated a lot on the analysis of telomere lengths from Dolly’s chromosome. They found out that the three years old Dolly’s telomeres were much shorter than the other normal sheep of similar age (Shiels, Kind and Campbell, 316). Despite Dolly’s telomeres being genetically identical to Fin Dorsett mother, the telomeres could not adequately perform their function, which entailed protection of the end of chromosomes, to prevent them from losing their respective genes during cell division. Thence, this explains the sudden death of Dolly, ascribed to shortening of telomeres through cell division. The chromosome will easily experience corrosion, and quicken the aging period (Miyashita, 1650). Apart from this, the cell can also undergo abnormal division that can amount to cancer, and faster aging in cloned organisms. This was yet confirmed by another research that included the measure of the telomere length and telomerase activity in cloned cattle and pigs (Jeon, Hyun, Lee, Kim, Kim, Jeong, Kang, Lee, Han, Ahn and Hwang, 316). The researchers found out that the shorter telomerase on cloned cattle and pigs increased the aging rates of the organisms (Jeon, Hyun, Lee, Kim, Kim, Jeong, Kang, Lee, Han and Ahn, 28). On the other hand, other researchers showed that the chromosomes from cloned cattle and mice had longer telomeres than normal. Therefore, telomere lengths were not the main reason in determining the life expectancy of a cloned organism (Wilmut, Schnieke, Mcwhir, Kind and Campbell, 812). Although there is some evidence that telomere length is connected to aging, researchers still argue that it is not possible to predict the age of cloning animals.
Dolly's appearance inspired the possibility of human cloning. However, cloning technology was in disparity with the social and human ethics. Asexual reproduction or cloning of mammal was encrypted as a procedure that would otherwise destroy and render useless the traditional and natural system of reproduction. The offspring reproduction of mammal goes through sexual reproduction, which is a process that requires both mammal parents’ gametes-sperm and egg. The sperm and egg conflate together through fertilization to form a zygote. The subsequent stage involves cell division of the zygote that develops to embryo.
Conversely, the hereditary information is from sperm and egg, whereby each gamete provides half the hereditary information, and, therefore, the offspring display traits and characteristics of both parents. The combination of traits and characteristics from both parents determines the traits of the offspring in comparison to both parents. As science advances, there is the establishment of artificial insemination fertilization techniques, an artificial fusion of sperm and egg.
The idea of cloning has faced a lot of criticism, and the majority of the population believes that cloning technology when used in human may cause a change in the transitional fertilization and the role of males will not necessary into reproduction system, defying the rules of nature. Doerflinger, a catholic ethicist, affirm that cloning of human will distort the structure of family, killing the procreation system (1). He further asserts that cloning is best meant for commodities rather than human beings (2). Doerflinger, still attests that clones are not peoples’ children, nor brothers and sisters, and it could lead to the deformation of the legendary family trees of most families (3).
Regardless of the ethical issues, safe and acceptable somatic cell nuclear transfer technology can be developed to increase the survival rate of the cloned embryo, and solutions for the cloning abnormalities (Wilmut, Schnieke, Mcwhir, Kind and Campbell, 813). This can be largely achieved through ensuring that cloned animals are similar to non-cloned animals, in every aspect of genetic makeup and characteristics, and the organisms also have health and wellbeing life. Developmental defect genes and chromosomes in the cloned animals should be minimized once detected, to increase the life span of the clone and consequently have significant benefits from the cloning development (Wilmut, Schnieke, Mcwhir, Kind and Campbell, 813). In the same line, improvement of the cloning process can be attained through modifications of the basic NT manipulation procedure (Oback et al, 5), the choice of an appropriate donor cell (Oback and Wells, 147) and recipient cytoplast (Hiendleder et al, 1196). Further, embryo culture media formulations (Chung, Mellissa, Marisa and Latham, 1178), and control of reprogramming can also be used (Collas and Hakelien, 354).
The research that points out the various possibilities of cloning is based on the telomerase of chromosome. Only this factor can be provide and explain the actual age of Dolly. So far, understanding of the aging and health problem are limited to observations of the telomere lengths of the animals (Xu and Yang, n. p.). The telomerase activity of the cell and embryos, and the correlation between many factors-like donor cell type, culture and time-with telomere lengths, aid in the prediction of serious health problems of the cloned organisms (Xu and Yang, n. p.). Exclusively, the eight species: cow, mouse, pig, goat, rabbit, cat, mule and horses have been cloned since dolly, somatic cell nuclear transfer, and they have affirmed that the earlier process is still an extremely efficient process (Liu, n. p.).
Concisely, the establishment of Dolly’s has brought a new revelation in the world of science. Its birth and death has led to the refocusing of the attention on whether cloned animals and perhaps humans is of any significance, raising the undoubted possibility for therapeutic application in humans. Moreover, the whole idea issues Scientists with the ability to copy healthy cells and furbish up genes that cause diseases, and similarly, generate new organs for instance skin and heart, to aid in treating people with skin and heart related illness. Individuals who cannot have babies might also be helped. Many scholars support the scientist to replicate human cells for research, or copy organs for transplantation. Most of The scholars believe cloning human embryos for research is not immoral, despite criticism by religious leaders, who consider that cloned human embryo is tantamount to termination of life. Nevertheless, cloned animals always have abnormal development, and researchers obtained a lot of serious abnormalities on some cloned animals. These events have discouraged scientists on applying the cloning technology on human, and they believe that cloning human is a hazardous procedure, accompanied with vital and inestimable impacts that can terminate the human generation.
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