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Somatic Cell Nuclear Transfer
One of the basic techniques used by scientists is the Somatic Cell Nuclear Transfer (SCNT). This technique has been used by scientists for many years to clone animals from embryonic cells. As the name of the technique implies, transferring of a somatic cell is involved in this process. A somatic cell is any body cell, such as a skin cell, that forms tissues and organs of the body. All the cells in an animal, with the exception of sex cells, are somatic cells. This somatic cell is then inserted into a recipient cell.
The recipient cell is usually an unfertilized egg that is taken from an animal soon after it has ovulated. Before inserting the somatic cell, the scientist must remove the chromosomes, which contain genes and function to carry on hereditary information, from the recipient cell. This step is done with an extremely fine micropipette.
After inserting the somatic cell, the two cells fuse together. Occasionally, the fused cell will begin to develop like a normal embryo, producing offspring if placed in the uterus of a surrogate mother for further development.
Problems associated with the SCNT technique are the stress on both cells involved in the process. This results in a high mortality rate of recipient eggs. In addition, the entire process is time and resource-consuming, because parts of it require manual labor under a microscope. Similar to other techniques, it is also inefficient in that only approximately 2% of embryos ever survive to become live offspring, and even then, many of those that do survive die shortly after birth. As of 2004, the causes of the losses are unknown.
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