Jorge Luis Villanueva Aguilera.
Essay about “Human Cloning”.
May 12, 2011.
Should humans be cloned?
That is the question that many people all over the world have been debating. Some say it is morally wrong, that we would be nefariously attempting to "Play the role of God." However, the facts have shown that there is nothing inherently wrong with human cloning. Scientists have proved anumber of times that human cloning would be nothing but beneficial to the human race, if only it was legal. If the law allowed human cloning, it would not only save lives, but it would lead to a number of advancements in scientific research, and improve the quality of life.
In the past century, scientists have been assiduous workers in making numerous achievements, discoveries, and inventions,giving us the knowledge we have acquired about ourselves and about the world around us. For years, scientists have studied and made tremendous progress in cloning. For example, AIDS. This is a wellknown illness that damages the human immune system. There are treatments available, but statistics show that three million people die from AIDS each year, and yet so far, no one has been able to find acure. With cloning, scientists could copy and create more white blood cells to fight off and kill the deadly virus.
What is Human Cloning?
The simplest explanation of human cloning is the creation of a copy of another human being without involving sexual reproduction using sperms and eggs. How is this done? In this case the nucleus of a cell, that is, from the donor (which has to be cloned) isisolated from the cell. This nucleus is then inserted into an egg whose nucleus has already been removed. The egg is then subjected to chemical treatment or jolts of electricity. This results in the integration of the donor nucleus with the host egg and triggers cell division. Once a desired level of cell division has been achieved by the egg, which is now referred to as the zygote, it is implantedin the surrogate mother using the technique of in-vitro fertilization. This type of cloning is known as reproductive cloning or embryo splitting and it is a successful method. Dolly (a sheep) was created with this method.
The other type of cloning is therapeutic cloning. In this procedure, instead of implanting the embryo into a mother's womb, the embryo is grown to develop into stem cells.These stem cells could then be grown into organs of the human body like the skin, liver and heart. These organs would then be used to replace the original defunct organs of the donor. Therapeutic cloning holds promise to those suffering from degenerative nervous system disorders like Alzheimer's and Parkinson's. Since the new organ would be created from the genetic material of the person sufferingfrom the disease, his body would not reject it. Therapeutic cloning and embryonic stem cell research are being explored by scientists to provide answers to a number of diseases of mankind.
Nuclear transfer, a little bit of history
* 1900’s – Hans Spemann speculated that nucleus from 8-cell fetus would produce a clone if transferred to enucleated ovum prior to implantation.
* 1952-53Briggs and King developed nuclear transplantation technique and successfully cloned tadpoles from skin cell of fetal tissue as donor (success rate very low).
* 1993 – Tsunoda, Kato, and Cheong-nuclear transplantation of mouse embryos (8-cell stage), adult mice developed.
* 1997 – Ian Wilmut – nucleus of an adult female sheep mammary gland cell transplanted into enucleated egg. Live birth oflamb (Dolly); demonstrates ability of adult cell (differentiated) to direct development of normal, cloned organism Success rate very low (1 of 227).
* 1997 – Oregon Regional Primate Research Center - Two Rhesus monkey clones (Mimi and Kiki) born after nuclear transplantation from 8-cell embryo
* 1999 – Richard Seed, M.D. announces plans to develop nuclear transplantation technique for...
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