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Human oocytes made in the laboratory this way could bring the idea of therapeutic cloning nearer to reality. This is the concept that physicians could generate new body tissues for a patient by taking a cell from the patient’s skin, inserting the cell’s nucleus into an oocyte whose own nucleus had been removed, and letting the oocyte develop into an early embryo. Stem cells could be taken from the embryo and induced to develop into heart muscle cells genetically identical to the patient’s own.
http://www.nytimes.com/2003/05/02/science/02STEM.html