What is it? Mammal cloning is the process of taking somatic cells from a donor (cannot be nerve cells from CNS or red blood cells because they do not continually divide) and stripping it of its nucleus. It is the placed into an egg cell to be developed within a surrogate mother. In order for this happen, the cells must be exposed to the least amount of mutagens possible.

There are currently three methods to animal cloning. 1.Splitting off a cell from an embryo (twinning): An egg is fertilized normally and divides. Some cells are then taking and placed in a different mother. 2.The Roslin technique: This technique consists of a donor cell and an oocyte. The nucleus is removed from the egg cell and replaced with the nucleus from the donor cell (cell fusion, transplantation). The embryo is transplanted into mothers. 3.The Honolulu technique: This process uses adult cells and nuclei. After the nucleus is transferred from the donor cell to the egg, the cell is jumpstarted (through chemical culturing) to create embryos that are placed into surrogate mothers for development.

Clones are genetically identical copies with the same genetic information. Although they have the same genotype, they may not necessarily have the same phenotype due to environmental conditions (nature vs. nurture).

Where does it originate? Cloning of plants has been a very common practice for hundreds of years. Small animal cloning has dated back to the 1960s. After the cloning of Dolly (the sheep- discussed later), many larger animals have been cloned. The idea of the possibility of human cloning has also been debated.

How has it been used? 1996: Scottish researchers produced Dolly (from an utter cell of 6 year old sheep). 1998: Japanese researchers attempted to clone eight calves from one cow. Only four survived.

How is it helpful? Cloning can be used to produce animals for medical research purposes. Although human cloning is not yet available due to ethical concerns, some researchers say it can be used to help sterile couples have children. It can be used to create genetically identical animals that have a specific desired gene or phenotype (such as healthy milk-producing cows). The Dolly researchers were able to clone genetically modified sheep to produce better milk containing human proteins that are essential for blooding clotting.

2008: FDA approved that all products coming from cloned animals are safe for consumption. Cloning can also be used to test new drugs because identical organisms can produce identical reactions. This helps researchers to understand the actual effects of the drug. Researchers are also focusing on the prevention of extinction or endangered species through cloning. Questions have arose regarding the restoration of the woolly mammoth through tissue that has remained alive in the laboratory. Some may even chose to clone their deceased pets (as in the case with CC the cat.

Researchers are also attempting to use therapeutic cloning: an embryo is cloned from stem cells with the same DNA as the donor cell. This can help with understanding and the prevention of certain diseases.

With human cloning, researchers could be rid of defective genes (cloning of healthy human cells). Traumatic injuries can be healed faster through cloning of that person's cells.

What are the potential problems? Most cloned animals do not survive. Dolly was the only one out of 227 cloned embryos to survive. Often times, there is an increase in birth size and faster aging. There are concerns with organ defects. Premature aging and immune system problems can also occur.

What are the ethical considerations? With therapeutic cloning, there are issues and concerns related to the destruction of cloned embryos. Stem cells are gathered at blastocyst stage of development (first five days after development) Cloning may also reduce genetic variation in animals. There are some concerns with creating genetically identical people that go against religious or societal values. Most religions agree that life can only begin at conception, and can be formed only by the uniting of a male and female. Some religions view humans as being created by God, so people,do. It have the right to attempt to create a human being.

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