Cloning Cloning Is the Exact Replication of Term Paper
- Length: 15 pages
- Subject: Genetics
- Type: Term Paper
- Paper: #53706370
Excerpt from Term Paper :
Cloning? Cloning is the exact replication of a single individual gene or a part of a single individual gene achieved with the use of specialized DNA technology. The result may be used for further scientific research or for nay other purposes that it was cloned for. The Human Genome Project that conducts cloning experiment on a regular basis refers to the entire process as the method of 'cloning DNA', and the cloned or the copied DNA molecules are called 'clone libraries'. Another type of cloning method is that whereby the entirely 'natural process of cell division' is utilized to make numerous copies of one single cell. In this particular process, the genetic makeup of the particular cell that has been cloned will be the exact same replica of the original cell from which the copies were made, and this is referred to as the 'cell line'. The third type of cloning involves the process of making complete and genetically identical animals, one example of which is the famous Scottish sheep that was cloned, Dolly. (Genome Glossary)
When Dolly was created, in the year 1997, there was a worldwide interest and concern and also a certain amount of controversy, as only expected. The very possibility that cloning could be applied to human beings raised quite a few eyebrows and the scientific and ethical considerations behind such an eventuality became major issues that took up a lot of time and energy. In fact, when the sheep that was cloned actually lived, it was termed as the breakthrough of 1997, and raised numerous questions as to what exactly 'cloning' is, and how it can be done. The three types of cloning as stated earlier, are 'recombinant DNA technology', 'reproductive cloning', and 'therapeutic cloning'. The recombinant DNA cloning is also referred to as 'molecular cloning' and 'DNA cloning', and also as 'gene cloning'. (Cloning Fact Sheet)
The technical process is like this: the DNA fragment of interest is transferred from any particular organism to a self-replicating genetic element that is also called a 'bacterial plasmid'. After this, the DNA can be propagated in a foreign host cell, and this means that it will then create a completely identical replica of the original cell, eventually. Generally, scientists who are studying a particular gene will use a bacterial plasmid in order to generate and produce several copies of the same gene. Plasmids are noting but self-replicating extra-chromosomal circular DNA molecules, and this is different from the normal ordinary bacterial genome. Therefore, when undertaking the process of cloning a gene, the scientist initially isolates the DNA fragment that contains the gene of interest by using certain restriction enzymes, and then uniting them with a plasmid that has been treated with the very same restriction enzymes. After this process, the fragment of chromosomal DNA will combine with its cloning vector in the laboratory, and at this stage it will be known as the recombinant DNA molecule. This will then be introduced into a suitable host cell, and this will in turn produce the recombinant DNA as well as the host cell DNA in a suitable combination. (Cloning Fact Sheet)
It is a fact that plasmids can contain up to 20,000 bp of foreign DNA. The second type of cloning process is that of 'reproductive cloning', and this will be used to generate or produce another animal that has the same nuclear DNA as another animal that was already living. The animal Dolly was reproduced using this method of cloning. In the method, also referred to as 'somatic cell nuclear transfer', or in other words, SCNT, the genetic material from the nucleus of a donor adult cell will be transferred to an egg whose nucleus, or n other words, its entire genetic material, has been eliminated previously. Thus the egg is reconstructed using the material that has been obtained from the donor cell, and it must be treated with certain strong chemicals or even electric current so that the process of cell stimulation will be started. An embryo is formed, and this will be transferred to the uterus of a female host, where it will progress in a natural way until it is born in the natural way. This was the process that made Dolly, the cloned sheep.
What makes the process amazing is the fact that it could be proved beyond doubt that the genetic material from a specialized adult cell could in fact be re-programmed in order to create an entirely new organism. The third type of cloning is referred to as 'therapeutic cloning', and is the process by which human embryos are used in scientific research. What has been often misunderstood is the fact that the process is used to create another human being. The truth is that therapeutic cloning is not meant to create another human being, but to harvest the human stem cells so that the result can be used for such scientific purposes, such as the best method to treat a particular disease, and the study of human development, and so on. Stem cells are extremely important to a scientist and to a biomedical researcher because of the fact that they are capable of regenerating virtually any type of specialized cell that may be present in the human body. These stem cells are generally extracted from the body after the cell division has been taking place for about five days, at which stage the egg is known as a 'blastocyst'. (Cloning Fact Sheet)
What is crucial here is that at the time of extraction, the embryo would have to die or give up its life, and this is taken as an issue of grave concern by the ethical and moral brigade. Researchers however contend that when the technology of extracting stem cells has been perfected, it would be possible to treat heart disease, cancer, Alzheimer's, and other often incurable diseases with the help of stem cells. They also hope that the extraction of stem cells would serve to generate tissues and also organs for the purpose of transplanting them into a human body, an amazing miracle that would not be possible if the extraction of stem cells were to be banned. When an organ needs to be generated, the DNA from the person with the disease would be extracted and inserted into an enucleated egg, after which the egg starts to divide. After the division has been taking place for some time, the embryonic stem cells could be utilized for organ transplantation because of the fact that it is at this important stage that the embryonic stem cells can be changed and transformed into the patient without having to face the possibility and the very real risk of tissue rejection that is a major cause for the failure of organ transplantations.
This is because of the simple fact that when the stem cell extraction method is used, the resulting cloned organ would match the genetic profile of the recipient. Therefore, when cloning is performed, then organs could very well be generated from cloned human embryos, and this could also mean that the need for organ donation could be reduced and over a period of time, even eliminated totally. In November 2001 scientists from Advanced Cell Technologies- ACT announced that they had managed to produce a human embryo for the purpose of therapeutic research. The method that they used was this: eggs were collected from a number of women's ovaries with a minute needle, and a skin cell was effectively inserted into the enucleated egg so that it would serve the purpose of a brand new nucleus. A chemical referred to as 'ionomycin' was used to provide appropriate stimulation to the egg so that it could start to divide, and soon the process of cell division began, with very limited success. Although eight eggs were used in the study, only three began to actually divide, and even then, only one egg was able to divide into six cells before it stopped too. (Cloning Fact Sheet)
Though cloning may have its benefits and advantages, but however important and beneficial the process is, is it really moral to go about cloning another human being or even an animal? There has been immense and intense debate on this issue, and there has been no conclusion reached as yet on the important question of whether cloning is moral and ethical. It must be remembered that plant cloning has been going on for many years in the past, and it was only when animal cloning was successful, in the form of the cloned sheep, Dolly, that the entire world sat up and took notice and stated that it was not morally right to clone a life. Bob Gast, the Acting Vice President of Research and Graduate Studies at MSU said that though it was indeed a great breakthrough for the staff at MSU, it was doubtful as to whether they would continue the research, because of the moral implications in the subject. (U community members debate morality…