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Transgenic Technology Cloning Technique Essay Research Paper

Transgenic Technology: “Cloning” Techniques

Amanda Kruvand

Transgenic Technology Transgenic technology can introduce a gene or genes from one individual’s DNA into the DNA of another individual- even when the genes come from different species. The gene or genes are inserted in to a fertilized egg and become integrated in to the DNA of that zygote.

Nuclear Transfer Technology It is possible to replace a complete set of genes (called a genome) using nuclear transfer technology. The nucleus, which contains the genome, is taken from a fertilized egg cell when it is still a zygote (when it is still one egg cell and has not begun to differentiate). The genome of an unfertilized cell (called a gamete) is removed, and the nucleus from the fertilized egg cell is inserted in to the unfertilized gamete. This results in a new zygote, its nuclear DNA identical to the original zygote. The donor’s genome was not duplicated but only transferred from one egg cell to another. The donor egg cell never developed and no longer exists. If the new fertilized egg begins dividing, its cluster of new cells can be separated into individual egg cells gain, so that they divide and grow in to separate individuals, so it is possible to have two or more embryos with identical nuclear DNA. However, there is other DNA, called mitochondrial DNA, that is not inside the cells nucleus but in the mitochondria of the surrounding cytoplasam. This DNA is not transferred in nuclear transfer technology

Purposes This technology is currently being used to engineer mice to express human genes. Genes, such as cancer genes, are inserted on to the embryos of research mice. These transgenic mice express the human genes and can be used to test different treatments to see if they might be effective on humans. Transgenic technology can also be used to insert human genes into sheep, pigs, cattle, and goats so the animals would produce human proteins in their milk. Once extracted, these proteins would be useful for treating such human diseases as emphysema and cystic fibrosis. Organs, tissues, and blood might also be produced using this technology. The transplantation of animal organs to humans is called xenotransplatation, but is very difficult. For example, pig hearts are similar enough to human hearts that they could be transplantable in to humans, but they would be rejected as foreign tissue by a human recipient’s immune system. Perhaps using the DNA of a recipient, a transgenic pig could be engineered to produce a heart the immune system would not recognize as foreign. Thousands of patients awaiting organs might benefit from transgenic technology.

Problems Engineering organs and tissues in animals for transplantation to humans creates the danger of developing new zoonoses (diseases transmitted from animals to humans) and giving certain classes and cultures of people the ability to live longer.

Transgenic Technology: “Cloning” Techniques

Transgenic Technology Transgenic technology can introduce a gene or genes from one individual’s DNA into the DNA of another individual- even when the genes come from different species. The gene or genes are inserted in to a fertilized egg and become integrated in to the DNA of that zygote.

Nuclear Transfer Technology It is possible to replace a complete set of genes (called a genome) using nuclear transfer technology. The nucleus, which contains the genome, is taken from a fertilized egg cell when it is still a zygote (when it is still one egg cell and has not begun to differentiate). The genome of an unfertilized cell (called a gamete) is removed, and the nucleus from the fertilized egg cell is inserted in to the unfertilized gamete. This results in a new zygote, its nuclear DNA identical to the original zygote. The donor’s genome was not duplicated but only transferred from one egg cell to another. The donor egg cell never developed and no longer exists. If the new fertilized egg begins dividing, its cluster of new cells can be separated into individual egg cells gain, so that they divide and grow in to separate individuals, so it is possible to have two or more embryos with identical nuclear DNA. However, there is other DNA, called mitochondrial DNA, that is not inside the cells nucleus but in the mitochondria of the surrounding cytoplasam. This DNA is not transferred in nuclear transfer technology

Purposes This technology is currently being used to engineer mice to express human genes. Genes, such as cancer genes, are inserted on to the embryos of research mice. These transgenic mice express the human genes and can be used to test different treatments to see if they might be effective on humans. Transgenic technology can also be used to insert human genes into sheep, pigs, cattle, and goats so the animals would produce human proteins in their milk. Once extracted, these proteins would be useful for treating such human diseases as emphysema and cystic fibrosis. Organs, tissues, and blood might also be produced using this technology. The transplantation of animal organs to humans is called xenotransplatation, but is very difficult. For example, pig hearts are similar enough to human hearts that they could be transplantable in to humans, but they would be rejected as foreign tissue by a human recipient’s immune system. Perhaps using the DNA of a recipient, a transgenic pig could be engineered to produce a heart the immune system would not recognize as foreign. Thousands of patients awaiting organs might benefit from transgenic technology.

Problems Engineering organs and tissues in animals for transplantation to humans creates the danger of developing new zoonoses (diseases transmitted from animals to humans) and giving certain classes and cultures of people the ability to live longer.




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