Sunday, April 27, 2008

Body I


Cloning originated in the early centuries as a way to better mankind. Cloning is a remarkable process. Scientists can take any cell from a human body, extract the DNA, and insert it into any fertilized egg and possibly have it develop into human beings (Williams). When I first thought about cloning I thought of myself being cloned; at the time I couldn’t really tell you why I just thought it was cool. I did not know that it was such a big controversy in congress. Scientists can take a strand of animal fur because it has the animals DNA in it, then they can make an exact copy of a specific animal the scientists are trying to duplicate. Reproductive cloning has been used for research purposes only, however in due time I think cloning could be used, and maybe work very effectively for repopulating endangered species or to make breeding of specific species easier.
It is important that cloning not slip into the hands of those that would take advantage of it; cloning should not be used for reproducing animal pets. Cloning must be reserved for research and reproduction only in extreme cases. Should cloning be used? “In some cases maybe, and that’s a strong maybe. If an animal is on the verge of becoming extinct then possibly, but to clone family pets absolutely not” (Williams).
There has been successful cloning throughout the years and a lot of non successful clones. Dolly the first mammal cloned from an adult animal in July of 1997 in Scotland is now dead (Bridget Kuehn); no one thought that Dolly would die that day, she ran about playing, very energetic then suddenly she died, no one knows the cause of death. Dolly was one of the first successful attempts at cloning. Since then goats, pigs, mice, cats, rabbits, etc… have all been cloned successfully, however chickens, monkeys, and horses are the most difficult to clone most attempts were pronounced a failure.
Cloning is an exact genetic copy of an organism. Reproductive cloning is performed today only for scientific research and with the intent of creating an organism. In reproductive cloning there is a process called Somatic Cell Nuclear Transfer “SCNT”, where the nucleus contains an organism DNA of a cell. Somatic cell nuclear transfer is not a dangerous process. The scientists remove a body cell rather than a sperm or egg cell from an organism and the rest of the cell is discarded.
If humans could be cloned, what would be the reason for humans to be cloned? A reason a person might want to be cloned is so that people will remember how the actual person looks in person rather than in a photograph. “We already live in an overpopulated world. It would be the line between family members. If clones are no longer a blending of a set of parents but just a copy of one individual’s DNA, then would it be legal for a brother and sister to marry? How would we define a species if we were able to clone ourselves”? (Williams). Humans are impossible to clone right now using the current techniques that the scientists use. Monkeys have been cloned, but the process is very difficult. Somatic cell nuclear transfer also is used in therapeutic cloning. Therapeutic cloning process is used for reproductive cloning as well. There has been a cloned embryo a couple years ago.
In the picture above it shows the process that is done in therapeutic cloning. Stem cells are important to biomedical researchers because they can be used to make a specialized cell in the human body for use. Therapeutic cloning aka “embryo cloning” is the production of human embryos for use in research. What ability does therapeutic cloning have? “it has the ability to build certain parts that are needed by an individual” (Williams). Therapeutic cloning is used to harvest an embryonic stem cell in medical treatments. The embryonic cell that is produced can be used to create skin for a burn victim or cells for those with spinal cord injuries. Stem cells are extracted from the egg after it has divided for five days. The egg at this stage of development is called a blastocyst which is a mammal embryo consisting of an inner cell mass, a cavity, and an outer layer (adobe acrobat). Many researchers hope that one day stem cells can be used to serve as replacement cells to treat heart disease, Alzheimer’s, cancer, stroke, and other diseases that are life threatening. I believe that one day researchers will find a way to cure uncureable diseases through stem cell research. Therapeutic cloning can work wonders on an individual. Therapeutic cloning can be used to generate tissues and organs for transplant (Woods). Therapeutic cloning has its limitations. The stress placed on both the egg cell and the introduced nucleus is enormous, leading to a high loss in resulting cells. There is a program named the Wellcome Trust which considers stem cell research and the development of new treatments for a wide range of life threatening diseases and conditions. Therapeutic cloning has a handful of steps to creating an organism. The first step is to place the eggs in a culture dish to mature; 2nd each of the eggs has a remnant cell called the polar body and cumulus cells from the ovary clinging to it. 3rd a selected egg is held still by a pipette which is a tube used in laboratories for measuring small amounts of liquids or transferring small objects. 4th A needle is then used to remove this small portion called the zona plug, 5th the needle then is used to go in side the hole that is created from the zona plug and take away the polar bodies and the eggs genetic material. 6th a fibroblast cell is taken up into this other needle from another egg. 7th the fibroblast is placed into the egg that had its genetic material removed. 8th the egg is injected it is exposed to chemicals and a number of growth factors so that it activates to divide. After 24 hours the activated egg begins to divide, the cells in the egg now contain genetic material. 4 or 5 days pass and a hallow ball of about one hundred cells has formed; it holds a clump of cells called the inner cell mass that contains stem cells. The Blastocyst is then broken open and the inner cell mass are grown in a culture dish to yield stem cells. The stem cells one day could grow into a variety of cells used to inject into a human. The picture above shows the process of therapeutic cloning of adult stem cells. Adult Stem cells are apart of therapeutic cloning they self replicate and give rise to more differentiated cells. Adult stem cells give the rise to limited types of cells. The number one goal for the adult stem cell is to maintain and repair the tissue in a living organism. The term adult stem cells refers to any cell that is found in a developed organism that has the ability to divide and create another cell like it self also divide to create a cell other than itself.

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