Cloning Essay Research Paper In 1938 a

Cloning Essay, Research Paper

In 1938, a German scientist, Hans Spemann theorized that organisms could be reproduced. His belief was that by transplanting the central element of one animal’s cell into the egg of another animal, the animal supplying the cell could be reproduced or “cloned.” Dr. Spemann believed that the central element or “nucleus” of a cell contained the genetic blueprint for the structure of an organism. In 1952, American scientists tested his theory by infusing the nucleus of a frog’s embryo into a frog egg but it resulted in failure as no frogs were developed. In 1970, the experiment was repeated by a British scientist and resulted in the development of some specimens, which died after reaching the tadpole stage. Since that time there have been several claims of cloning. Some were exposed as frauds, some produced “organisms” that died within days.

There has also been widespread cloning of several types of animals beginning in 1984. Why then was Dolly such as sensation when the world was told of here existence in 1997? In the past, clones were produced from embryonic animal cells. The new process is called somatic cell nuclear transfer, which is performed using nature cells. This is the process that may have produced Dolly and which some scientists feel can be used to produce human clones (Scientists 143).

It has been publicized that Dolly was produced after 277 failures. What happened to the failures? The team of scientists that produced Dolly explained that they removed cells from the under of an adult sheep, starved those cells of nutrients for several days so they would enter a dormant state and then used an electrical charge to force the pores of the cells to open. They then fused together 277 different eggs and cells. Of those 277 fused eggs, only 29 survived and were implanted into 13 ewes, which would serve as surrogate mothers. Of those 29, only one sheep embryo survived. That embryo developed and was born in July of 1996 (Scientists 142). In February of 1997, the world was introduced to that sheep, which was named after country music performer, Dolly Parton. Well, Hello Dolly!


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