Genetics Essay, Research Paper
Genetic engineering, altering the inherited characteristics of an organism in a predeterminedway, by introducing into it a piece of the genetic material of another organism. Geneticengineering offers the hope of cures for many inherited diseases, once the problem of lowefficiencies of effective transfer of genetic material is overcome. Another development hasbeen the refinement of the technique called cloning, which produces large numbers ofgenetically identical individuals by transplanting whole cell nuclei. With other techniquesscientists can isolate sections of DNA representing single genes, determine their nucleotidesequences, and reproduce them in the laboratory. This offers the possibility of creatingentirely new genes with commercially or medically desirable properties. While the potentialbenefits 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 theinfluenza virus, could be hazardous. 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 unique. Is that idea undercutby cloning? That is, if you can deliberately make any number of copies of an individual, is eachone special? How special can clones feel, knowing they were replicated like smile buttons. “Wearen’t just our genes, we’re a whole collection of our experiences,” says Albert Jonsen. But theidea, 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 world of clankingFrankensteins, welded together made from used parts. Already there are thousands of frozenembryos sitting in liquid nitrogen storage around the country. “Suppose somebody wanted toadvertise cloned embryos by showing pictures of already born children like a product,” saysProf. Ruth Macklin, of New York’s Albert Einstein College of medicine, who specializes inhuman reproduction. Splitting an embryo mat seem a great technological leap, but in a worldwhere embryos are already created in test tubes, it’s a baby step. The current challenge inreproductive medicine is not to produce more embryos but to identify healthy ones and getthem to grow in the womb. Using genetic tests, doctors can now screen embryonic cells forhereditary diseases. In the not to distant future, prenatal tests may also help predict suchcommon problems as obesity, depression and heart disease. But don’t expect scientists to startbuilding new traits into babies anytime soon. The technological obstacles are formidable, andso are the cultural ones. Copies of humans are identical, but are the people the same? Probablynot. For a century scientists have been trying to figure out which factors play the mostimportant role in 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 twins rearedapart. Twins Jim Springer and Jim Lewis, separated at birth in 1939, were reunited 39 yearslater in a study of twins at the University of Minnesota. Both had married and divorced womennamed Linda, married second wives named Betty and named their oldest sons James Allan andJames Alan. Both drove the same model of blue Chevrolet, enjoyed woodworking, vacationedon the same Florida beach, and both had dogs named Toy.
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