Genetics
GeneticsThe process of cloning is the process of using the genes of a being to create another being genetically identical to it. Cloning technology has been called the "forbidden fruit of biology" (Begley 54). For years, scientists have been trying to perfect the cloning technique. In Scotland, scientists at the
Roslin Institute have finally succeeded. Their success comes in the form of a Finn Dorset ewe named Dolly. Dolly is a clone. Now that the cloning of mammals from body cells has been accomplished, we are forced to consider what stand must be taken on the issue of cloning human beings, and also examine the
effect of popular culture on our perceptions of cloning.
Dolly’s case is not the first example of cloning. A man named Hans Spemann first envisioned cloning in 1938. He suggested transferring the nucleus of an embryo into another egg. As early as 1952, two scientists, Robert Briggs and T.J. King attempted what Spemann had suggested with a frog embryo and egg. Unfortunately, the frog egg did not develop. (Specter/Kolata)
That same year, researchers in Pennsylvania cloned a live frog. The technique used was known as embryo twinning, or causing the embryo to split apart. It is much easier to clone with embryonic cells. Much later, mammals such as sheep were cloned using this process. (Nash 64)
In 1970, John Gurdon repeated the procedure suggested by Hans Spemann. This time, the experiment yielded partial success. The tadpoles were born alive, but they died when they began to feed. He showed that transplanted nuclei reverted to an embryonic state.
In the early 1980's, there was some controversy over the reported cloning of mice. Karl Illmensee and Peter Hoppe claimed that they had cloned mice from embryos. Other scientists tried to repeat their success, and they reported that mouse embryos could not be used for cloning after reaching the two-cell stage. The claims of Illmensee and Hoppe were discredited. (Specter/Kolata)
In the 1980's, biologists at Allegheny University of the Health Sciences cloned tadpoles from the red blood cells of an adult frog. The tadpoles could swim and eat just like normal tadpoles. They grew hind limbs, but died halfway through metamorphosis. (Nash 64)
In1993, defective human embryos scheduled to be discarded by a fertility clinic were cloned. Scientists teased apart the cells from seventeen embryos (each two to eight cells in size) and grew each cell separately, ending up with several genetically identical embryos. (Begley 54-56)
In 1994, calves were cloned by Neal First from embryos that had grown to at least 12 cells...
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