Реферат: Cloning

– Genetic Engineering Essay, Research Paper

CloningGenetic engineering, changing the inherited characteristics of an organismin a predetermined way, by introducing into it a piece of the geneticmaterial of another organism. Genetic engineering offers the hope of curesfor many inherited diseases, once the problem of low productiveness ofeffective transfer of genetic material is overcome. Another development has been the refinement of the technique called cloning, which produces large numbers of genetically identical individuals by transplanting wholecell nuclei. With other techniques scientists can isolate sections of DNArepresenting single genes, determine their nucleotide sequences, and reproduce them in the laboratory. This offers the possibility of creatingentirely new genes with commercially or medically desirable properties.While the potential benefits of genetic engineering are considerable, so may be the potential dangers. For example, the introduction of cancer-causing genes into a common infectious organism, such as the influenza virus, could be dangerous. We have come to believe that all human beings are equal; but even more firmly, we are taught to believe each one of us is special in our own way. That ideas seems to me to be undercut by cloning. That is, if you can deliberately make any number of copies of an individual, is each one special? How special can clones feel,knowing they were replicated? When anesthesia was discovered in the 19th century, there was a speculation that it would rob humans of the transforming experience of suffering. When three decades ago, James Watson and Francis Crick unraveled the genetic code, popular discussion turned not to the new hope for vanquishing disease but to the specter of genetically engineered races of supermen and worker drones. Later, the arrival of organ transplants set people offspringing about a world ofclanking Frankensteins, put together made from used parts. Splitting an embryo might like seem a great technological leap, but in a world where embryos are already created in test tubes, it?s a baby step. The current challenge in reproductive medicine is not to produce more embryos but to identify healthy ones and get them to grow in the womb. Using genetic tests, doctors can now screen embryonic cells for hereditary diseases. In the near future, prenatal tests may also help predict such common problems as obesity, depression and heart disease. The technological obstacles are appalling, and so are the cultural ones. Copies of humans are identical, but are the people the same? Probably not. For a century scientist have been trying to figure out which factors play the most important role in the development of a human personality. Is it nature or nurture, heredity or environment? The best information so far has come from the study of twins at the University of Minnesota. Twins Jim Springerand Jim Lewis who were separated at birth in 1939, were reunited 39 years late in a study of twins at the University. After looking at there background they found out that both had married and divorce women named Linda. The married second wives named Betty and named their oldest sons James Allan and James Alan. Both of them drove the same model of blue Chevrolet, enjoyed working, vacationed on the same Florida beach, and both had dogs named Toy. This is weird stuff.

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