Cloning
The History of Cloning and Genetic Science
Trying to control genes is almost as old as civilization, though they didn't exactly view it the same way. Now people talk about genetically engineered "Frankenfood," and wonder if what they're eating has been cloned, had unknown DNA inserted into it, etc. Long ago, though, early attempts to grow better crops, grafting, cultivating hybrids, breeding better livestockcthese were all really doing in a less precise way what scientists are attempting today. In 1866, Gregor Mendel told the world about his pea plants and about heredity, how information is passed down from one generation to another. In 1882, a German scientist saw what we now know as chromosomes inside salamander cells. In 1926, scientists found out that X-rays could cause genetic mutations in fruit flies. The first animal to be cloned was a tadpole, in 1952, cloned from an embryo. In 1953, two scientists discovered the double-helix structure of DNA. In 1969, the first gene was isolated, and the next year, researchers fabricated a gene themselves. In 1973, researchers inserted a gene from a toad into a bacterium and it began to work. This was the first so-called genetic engineering. In California, in 1976, human DNA was put into mice eggs who, along with their offspring, were used to study human disease. Two years later British doctors successfully fertilized an egg and put it in a woman's womb. She brought to term the first "test-tube baby" in 1978. In the same year, the gene which regulates the body's insulin was duplicated or "cloned" and in 1982, a drug was approved, which uses insulin produced by genetic engineering. The human insulin gene was placed inside bacteria which then produced the insulin. In 1984, genetic "fingerprinting" of people was introduced, where people can be identified by their DNA, and the technique was used the next year in a criminal investigation. In 1987, cows and sheep were cloned from embryos. This did not result, though, in perfectly identical, genetically controllable animals. The Human Genome Project is launched in 1990. In 1995, J. Craig Venter identified all of the genes in a bacterium. This gave a boost to people hoping to map human genes. People said it would take 10 years to accomplish. The next year Dolly was born, the first animal to be cloned from adult cells. The now-famous sheep was introduced to the world a year later in 1997. Late 1998, eight calves were born to Japanese researchers looking for the perfect cow. Their success rate of eight animals born for ten implanted embryos was a much more encouraging number than that of Dolly's experiments. Dolly was the first of 277 embryos to survive to birth. Also in 1998, Hawaiian scientists cloned a mouse and then cloned the cloned mouse again, three-times over, and other scientists succeeded in cultivating "stem cells." In June 2000, a rough draft of the map of the human genome was announced. 
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