Cloning literally means 'making a copy'. In the context of animal or human cloning, it is the technique by which an individual's exact genetic copy is made.
A normal embryo is formed by the fusion of a male's sperm with a female's egg. The resultant cell then divides into many cells by a biological process called mitosis. These cells have genetic information coded in the form of DNA molecules, which are derived from both parents.
In cloning, the genetic material in the egg cell, taken from the female is removed. The genetic material of a non-reproductive or 'somatic', cell taken from, for instance, the skin of the ear of the person to be cloned is then inserted into this empty egg cell. The process is completely asexual, in that it does not require any reproductive cell other than the enucleated ovum. The resultant egg with the donor's duplicate genetic material is then implanted into the uterus (womb) of the female.
Cloning and other Assisted Reproductive Techniques
Many treatments for infertility have been in use for some years known by acronyms such as IVF, ICSI, ZIFT and GIFT. In most of these procedures, an egg is fertilised by a sperm outside the woman's body and the resulting zygote is implanted back into her uterus. All the manipulation is done at the cellular level and both the sexes are involved. There is no direct interaction with the genetic material. Cloning is different in that it does not require the presence of a male gamete. The genetic material from any of the cells of the person to be cloned can be taken.
The advantages of cloning
According to its proponents, cloning has some major medical benefits. For instance in incurable diseases like leukaemia where a bone marrow transplant is the only option, a clone may be a perfect donor since he or she will be a perfect genetic match. Also where couples are incapable of producing children and want a child of the same genetic makeup, as their own cloning may be the best option.
The disadvantages of cloning
As with any new technology, there are apprehensions about the procedure. Those opposing cloning feel that it might bring a world into existence characterised by individual sameness rather than differences. If everyone was to have a clone, there may be no personality differences either.
Another issue, which might arise, is of eugenics, manipulation of the genetic code in a way so that only 'superior' children are born.
Further it has been the experience in animal experiments that several attempts have to be made before a 'normal' clone is achieved and the 'unsuccessful' results have had gross abnormalities in size and shape. In the human situation, this would be a horror in case it were to happen.
Other ethical issues
A unique feature of a clone would be that it would not just be a copy of the person who has been cloned. He or she would be a 'delayed twin'. For example, if A were to be cloned and B were to be his clone, B would be born 9 months after the procedure was initiated. B would an identical twin of A but born at a different time. However, A would also be a parent of B. Thus there would be a dual relationship between the two that is, A and B would be siblings genetically and parent and child socially.
Social scientists fear that the individuality of the child who is a clone may be undermined. Born looking exactly like one of the parents, having certain characteristic behaviour patterns and the pressure of 'being' like one of the parents might prove a major hindrance to development. Experts fear that a clone-child may be deprived of certain natural experiences. For example, if a sportsman were to be cloned, he might be deprived of any form of education or experience, other than that required to make him into a sportsman.
Most Western countries are imposing a ban on human cloning trials because of these ethical problems. However it will be impossible to stop the many surreptitious attempts, which will take place.
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