Реферат: Genetic Engenering Essay Research Paper Genetic Engineering
Genetic Engenering Essay, Research Paper
Genetic Engineering Genetic engineering, altering the inherited characteristics of an organism in apredetermined way, by introducing into it a piece of the genetic material of anotherorganism. Genetic engineering offers the hope of cures for many inherited diseases, oncethe problem of low efficiencies of effective transfer of genetic material is overcome.Another development has been the refinement of the technique called cloning, whichproduces large numbers of genetically identical individuals by transplanting whole cellnuclei. With other techniques scientists can isolate sections of DNA representing singlegenes, determine their nucleotide sequences, and reproduce them in the laboratory. Thisoffers the possibility of creating entirely new genes with commercially or medicallydesirable properties. While the potential benefits of genetic engineering are considerable,so may be the potential dangers. For example, the introduction of cancer-causing genesinto a common infectious organism, such as the influenza virus, could be hazardous. Wehave come to believe that all human beings are equal; but even more firmly, we are taughtto believe each one of us is unique. Is that idea undercut by cloning? That is, if you candeliberately make any number of copies of an individual, is each one special? How specialcan clones feel, knowing they were replicated like smile buttons. “We aren’t just our genes,we’re a whole collection of our experiences,” says Albert Jonsen. But the idea, he adds,raises a host of issues, “from the fantastic to the profound.” When anesthesia wasdiscovered in the 19th century, there was a speculation that it would rob humans of thetransforming experience of suffering. When three decades ago, James Watson and FrancisCrick unraveled the genetic code, popular discussion turned not to the new hope forvanquishing disease but to the specter of genetically engineered races of supermen and
worker drones. Later, the arrival of organ transplants set people brooding about a worldof clanking Frankensteins, welded together made from used parts. Already there arethousands of frozen embryos sitting in liquid nitrogen storage around the country.”Suppose somebody wanted to advertise cloned embryos by showing pictures of alreadyborn children like a product,” says Prof. Ruth Macklin, of New York’s Albert EinsteinCollege of medicine, who specializes in human reproduction. Splitting an embryo matseem a great technological leap, but in a world where embryos are already created in testtubes, it’s a baby step. The current challenge in reproductive medicine is not to producemore embryos but to identify healthy ones and get them to grow in the womb. Usinggenetic tests, doctors can now screen embryonic cells for hereditary diseases. In the not todistant future, prenatal tests may also help predict such common problems as obesity,depression and heart disease. But don’t expect scientists to start building new traits intobabies anytime soon. The technological obstacles are formidable, and so are the culturalones. Copies of humans are identical, but are the people the same? Probably not. For acentury scientists have been trying to figure out which factors play the most important rolein the development of a human personality. Is it nature or nurture, heredity orenvironment? The best information so far has come from the study of identical twinsreared apart. Twins Jim Springer and Jim Lewis, separated at birth in 1939, were reunited39 years later in a study of twins at the University of Minnesota. Both had married anddivorced women named Linda, married second wives named Betty and named their oldestsons James Allan and James Alan. Both drove the same model of blue Chevrolet, enjoyedwoodworking, vacationed on the same Florida beach, and both had dogs named Toy.