Cloning, the highly discussed scientific achievement of today, is considerd as the latest biological wonder. Years back people were wonder-struck to hear the news of test tube babies. But now Dolly and Bonny and similar oher products of cloning are hitting the headlines.
A clone can be defined as a group of genetically identical cells. A living being orginated from a single parent cell is also called a clone. The reproductive method through which a clone is created is called cloning. The modern science has proved that a new life can be created without the fusion of the egg and sperm. This can be considered as a type of asexual reproduction.Thus cloning can be conveniently defined as the creation of a new generation without the fusion of female egg and male spearm. In other words actually photocopies of the orginal parents are created through cloning.
Eventhough a prototype clone was xreated in 1952 the actual fully developed clone was created only in 1996. In the year 1952 two scientist namely Robert Brigs and Thomas Kinh created a clone tadpole from the cell taken from another tadpole. This is considerd as the first cloning conducted in an animal. But cloning was proved as a biological wonder only in 1996 by the creation of a sheepby name Dolly. The birth of Dolly at the Roslin Institute in Scotland on 5th July, 1996 marked a turning point in cloning reasearch. For the first time, a mammal had been successfully cloned from a cell nucleus taken from a ordinary tissue cell of an adult animal. Before this, the only success had been with nucleus from embroyonic cells.In the case of the formation of Dolly, a single cell extracted from a sheep of Welsh mountain genus was mixed with an egg cell of another sheep belonging to the Scotish Black Face genus. The D>N>A of the cell was removed before the fusion. The egg cell mixed with the single cellwas placed in the uterus of a third sheep and thus the Dolly was created. On 20th April, 1998. Dolly give birth to a child, Bonny through natural method proving that clone can lead a natural life.
1998 July 23rd issue of the Science Journal Nature reported the birth of 22 healthy and fertile female mice which have been cloned form a nuclei of adult overian cells using a technique similar to that used to produce Dolly. It is also reported form japan that twin calves wre born on 5th july, 1998 through cloning. They are named as Kaga & Nota and are amoung the five surviveing calves in japan out of 10 produced in the same way as Dolly.
The major achievement of cloning is that a new generation is created form a somatic cell of an animal. It is not necessary that a child forming by the fusion of sperms and egg through natural method, should retain as such the peculiarities of the father or the mother. Here thousands of genetic factors are combining together in the new child.
Some people are of opinion that a child forming through cloning cannot be considered as a new generation. It is nothing but the continuation of the parent cell. thus cloning questines even the process of birth and death according to few. Even with all these objections cloning experiments are in progress in a number of laboratories. But the intersting thing is that this method of cloning in humans is banned in many countryies especially the United States of America. We can hope that it will unveil a totally different face of the biological sciences of tomorrow.