Although it is historically known by scientists all over the world that cloning is originally a thing of nature, July 5, 1996 is a day recorded in history that many will never forget. On that day, at approximately 5:00 p.m., a sheep named Dolly entered the world. Dolly was a genetically engineered clone from the cells of an adult six-year old sheep. The process, known as nuclear transplantation, was created by a team of scientists led by Dr. Ian Wilmut at Roslin Institute in Roslin, Scotland. Dolly was indeed a miracle that would possibly open the scientific doors to human cloning and advances in medicine and biological research. Contrary to popular belief, cloning has been in existence prior to God’s creation of man. It all began thousands of years ago with many organisms of nature through a process known as asexual reproduction. However, by the late 20th century, scientists developed a method to manipulate an organism’s deoxyribonucleic acid (DNA), known as genetic engineering. This development led to the birth of animal clones and many ethical issues to follow. Cloning is defined as “a form of genetic engineering in which the DNA of a person, animal, plant, or even bacterium is used to produce a perfect or near-perfect genetic replica of the original” (Stanley, 2000a, p. 7). As stated earlier in the text, the history of cloning dates back many years ago. According to Encarta On-line Encyclopedia (2003), organisms—such as bacteria—reproduced asexually through a process known as fission. Various forms of yeasts would reproduce via bumps that would grow on the parent cell. These bumps would eventually receive a copy of the parent’s DNA and separate from the parent as a clone. Additionally, fruit-bearing plants—such as strawberries and various forms of grasses—would replicate themselves through their own stems that grew above ground. Man began to clone plants by taking “a cutting from one plant and placing it in a medium, such as earth or water, in which it would grow…” (Goodnough, 2003a, pp. 16-17). Farmers and experimenters began to try and make an “existing organism better by improving the medium in which it was reproduced or by mixing in elements that would make it stronger, bigger, more resistant to disease, and more likely to survive”(Goodnough, 2003a, p. 17). This process is known as genetic engineering. Scientists soon began to experiment with genetic engineering on invertebrates and amphibians: “Laboratory cloning techniques using undifferentiated embryo cells were first developed in the late 1800s, when German zoologist Hans Dreisch separated a sea urchin embryo when it was just two cells, and both cells grew to adults”(Microsoft Encarta Online Encyclopedia, 2003). Following Mr. Dreisch’s research, a German embryologist named Hans Spemann conducted follow-on experiments of Mr. Dreisch’s work using salamanders in which he determined that the “nucleus from a salamander embryo cell could direct the development of a complete organism” (Microsoft Encarta Online Encyclopedia, 2003). Following the successful completion of his experiment, Mr. Spemann made his results known to the public in 1938, at which time he proposed an “experiment to produce an animal by removing the nucleus from one cell and placing it into an egg cell with its nucleus removed” (Microsoft Encarta Online Encyclopedia, 2003). This is known as somatic nuclear cell transfer. In 1952, Mr. Spemann’s proposition came to fruition when two American biologists conducted the somatic nuclear cell transfer experiment on a frog embryo by inserting DNA from a frog embryo cell into a frog egg of which the nucleus had been removed. The experiment was a success. It is reported that nuclear cell transfer experiments were only successful if the “donor DNA was taken from an embryonic cell” (Microsoft Encarta Online Encyclopedia, 2003).
Ten years later, a British biologist named John Gurdon began conducting experiments using nonembryonic cells...
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