Cloning can be a very sensitive subject. It seems that it?s a battle between science and ethics. Does the ladder outweigh the former or vice versa? Maybe a few definitions will shed some light on the subject. ?Cloning is to create a genetic duplicate of an individual organism through asexual reproduction, as by stimulating a single cell? (Webster?s 211). ?Parthenogenesis is reproduction of organisms without conjunction of gametes of opposite sexes.? (Webster?s 800). Cloning has its medical uses, but do the ethical implications outweigh the advantages? The goal of genetic engineering is that every child be born strong, healthy, and well suited to make its way to the world. If genetic engineering would be used in this way the world would probably be a place of less disease. Sure it may be unethical to do some tests on humans, but without them medical progress would come to a halt. Cloning might also directly offer a way of curing diseases or a technique that could extend means to acquiring new data for the sciences of embryology and how organisms develop as a whole over time. Science has been trying for years to come up with cures for genetic diseases and so far haven?t really come up with anything that is truly helpful. On the other hand, with the technology of genetic engineering scientists may finally be able to start to understand the causes of diseases and to develop possible treatments and even prevention. For instance, the most studied disease is Cystic Fibrosis. Although, we have not found a cure yet, science ! might be getting close to coming up with a way of preventing Cystic Fibrosis. Science has made some major discoveries in the past forty years. In the 1960?s two French scientists by the names of Jacques Monod and Francois Jacob showed that genes can be turned on and off by what are called regulator genes. If it were possible to manipulate the regulator genes, than it would be possible to turn Cancer cells off and prevent it. It is expected that 185,000 people will be diagnosed with a brain tumor alone in 2000. That?s just brain Cancer, imagine how many lives would be saved if all Cancer cells could be turned off. Cloning isn?t just an advantage to the medical field. It would provide a link for a replacement to artificial insemination. Couples, who are unable to have children, or have genetic disorders, could use cloning to produce a child. Plus, women who are single could have a child using cloning instead of artificial insemination.
Natural cloning occurs too. All plants, some insects, algae, unicellular organisms that conduct mitosis or binary fissions, and identical twins are all clones of each other. As long as genetic make-up is the same they are clones, and a splitting embryo that creates two identical embryos produces twins. The difference between twins and clones, however, is that twins are new in genetic variation and unique from anything that came before them. Even if clones don?t have genetic variation they would closely resemble identical twins and more than likely would be accepted by the world as twins would. After all, there are some eight million identical twins alive today, so it is safe to say that about eight million ?human clones? are alive today. Plus, who is to differentiate between a clone and an identical twin? The world isn?t going to be able to distinguish between the two anyway.

Cloning is going to continue to be the subject of books, television shows, and movies. It has already been featured numerous times on the Discovery Channel and TLC. Dolly, the cloned sheep, was featured on the news for about four weeks. It is easy to get carried away and start thinking about what cloning will do to our future. However, it?s better to stop fantasizing about how human clones are going to take over the job market, but to look at what cloning has already done.

Thus far only the advantages of cloning have been described. It is only fair to know that cloning possesses some bad aspects as well. In case one didn?t know already genes are the basic units of inheritance. They are what make a plant, an animal, or a human being resemble its parents. Clones are carbon copies. They have the genetic information of only one parent. There is no mixing of genes with the chance of change. Therefore, clones would be deprived of a feeling of individuality and uniqueness. At least with natural reproduction genetic variation occurs and makes every person an individual. Without genetic variation everyone would be exactly the same and the world would be boring.

Not only will it erase individuality, which is almost bad enough in it, but also it will also eliminate the ?bad genes? and lead to dangerous narrowing of diversity in the gene pool. What does that mean? It means that if everyone is cloned over and over again off the same genes, there is a bigger chance of a mutated gene being prominent and then there would be no way to get rid of it. This is the main reason that science is reluctant to clone humans. So, what happens when we decline genetic diversity and the gene pool and we lose the ability to clone? Well, that?s simple we resort to a little process known as inbreeding. Inbreeding also increases the chance of transmitting mutated genes. In fact, zoologists and environmentalists trying to save endangered species are not having problems keeping population numbers up, but finding animals to breed that are not cousins.

Most scientists believe that cloning would create deformed or otherwise defective babies. For instance, some of the lambs produced by cloning before Dolly were larger than normal. It is very likely that defects would arise indeed for no other reason than the fact that the ability isn?t good enough to clone humans. ?The nucleus of a skin cell could have accumulated many genetic mistakes of no consequence to its role in the skin, but when asked to make a brand new organism these could prove deleterious in other tissues, or greatly increase the probability of developing cancer? (Beddington np).

Now that the advantages and disadvantages have been expressed the author feels that an example of the processes of cloning would be appropriate. The first example is the cloning of a frog.

1. The nucleus is removed from a frog egg. It is now called an enucleated egg. 2. A section of intestine is taken from a tadpole.

3. A cell from that intestinal tissue is taken and its nucleus removed. 4. The nucleus from the tadpole cell is put into the enucleated frog egg. 5. The egg, with its new nucleus, begins to divide and develop into a tadpole and then an adult frog. The frog?s genes are exactly like those of the tadpole because its instructions came only from the nucleus of the tadpole. The frog is a clone.

The next example of how cloning may be used is a cow embryo being shipped in the uterus of a rabbit.

1. Eggs are taken from a cow.

2. They are fertilized in a laboratory dish and begin to grow in the nutrient solution.

3. When they reach the hollow ball or blastula stage, each embryo is placed in a rabbit uterus.

4. The rabbit is shipped to another country...

5...and the embryo taken from the rabbit and replaced in the uterus of a cow. Thus far, the paper has listed the medical uses and ethical implications for cloning. Plus, an added bonus of processes in which cloning has been successful. Now, most people probably already have strong opinions about cloning and maybe this paper gave readers something on which to base their opinions. The goal of this paper wasn?t to convince the reader of cloning being advantageous or not, but instead to help people realize that the world is in store for some major technological advances and everyone must be prepared to deal with controversial issues such as the one presented above. If one is not able to deal with change then technology is just going to leave them behind. Like it or not technology is not going to stop progressing, so the world is going to have to learn to accept what is happening.

Nuclear transfer involves transferring the nucleus from a diploid cell ( containing 30-40,000 genes and a full set of paired chromosomes) to an unfertilised egg cell from which the maternal nucleus has been removed. The technique involves several steps (see diagram below). The nucleus itself can be transferred or the intact cell can be injected into the oocyte. In the latter case, the oocyte and donor cell are normally fused and the 'reconstructed embryo' activated by a short electrical pulse. In sheep, the embryos are then cultured for 5-6 days and those that appear to be developing normally ( usually about 10%) are implanted into foster mothers.

Nuclear transfer is not a new technique. It was first used in 1952 to study early development in frogs and in the 1980's the technique was used to clone cattle and sheep using cells taken directly from early embryos. In 1995, Ian Wilmut, Keith Campbell and colleagues created live lambs- Megan and Morag - from embryo derived cells that had been cultured in the laboratory for several weeks. This was the first time live animals had been derived from cultured cells and their success opened up the possibility of introducing much more precise genetic modifications into farm animals.

In 1996, Roslin Institute and collaborators PPL Therapeutics created Dolly, the first animal cloned from a cell taken from an adult animal. The announcement of her birth in February 1997 started the current fascination in all things cloned. Until then, almost all biologists thought that the cells in our bodies were fixed in their roles: the creation of Dolly from a mammary gland cell of a six year old sheep showed this was not the case and the achievement was voted Science Breakthrough of the Year at the end of 1997.

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Technology of Cloning
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