To explain in a scientific way, cloning means replacing the egg nucleus of an organism with the donor's nucleus. This nucleus contains unique genes of the donor. The procedure involves removing the nucleus of a somatic cell and inserting it into an enucleated or unfertilized egg cell. Unlike natural reproduction, wherein the egg contains a combination of genetic material, this egg which grows into an embryo contains only the donor's gene.
Theoretically, this might seem fairly straightforward. However, a high failure rate along with prevalence of high deformity and disability rates in cloned animals, strongly suggests cloning might not be applicable to humans.
~ It helps homosexual and sterile couples to have biological offspring.
~ It also helps in in-depth research, like motor neuron disease.
~ Embryonic stem cells can be cloned to produce tissues or organs to replace or repair the damaged ones.
~ Human cloning could allow parents who have lost a child a chance to redress their loss using the DNA of their deceased child.
~ Would he live like a unique individual or would he have to live like a genetic prisoner? Should parents choose the traits of a future child as is possible with cloning?
~ These and other such issues present an ethical and moral dilemma for scientists and experts alike who see cloning as a potential danger to human identity.
At the other end of spectrum are some experts who are of the opinion that the embryo does not require any particular moral consideration. They say that, at the stage when an embryo is cloned, it is just a bunch of cells that contain DNA, which are not very different from the millions of skin cells that we shed everyday. The embryonic cells at that stage cannot be considered equivalent to a human being because it does not have thoughts, self-awareness, memory, awareness of its environment, sensory organs, internal organs, legs, arms, and so on. They think that the embryo attains human identity or individuality much later during gestation, perhaps at the point when the brain develops so that it becomes aware of itself.
In view of the highly debatable aspects about cloning and weighing in on the pros and cons of this process, UNESCO passed a non-binding "United Nations Declaration on Human Cloning", in March 2005, which states: "Practices which are contrary to human dignity, such as reproductive cloning of human beings, shall not be permitted." In the United States there are no federal laws that ban cloning completely, yet 13 states have banned reproductive cloning. Although many countries have banned cloning, many countries allow therapeutic cloning, a system in which the stem cells are extracted from the pre-embryo, with the intention of generating a whole organ or tissue, so that it can be transplanted back into the person who gave the DNA.