WASHINGTON, Feb. 12 (UPI) -- Some U.S. researchers said Thursday they remain skeptical about claims by Korean scientists they had created human embryonic stem cells through cloning.
The scientists said they injected DNA material from the cells of women donors into the egg cells of the same women and used advanced technology to create cloned embryos. They then extracted stem cells from the embryos.
Embryonic stem cells are valued because they can grow into any type of tissue in the body and offer the possibility of repairing diseased or damaged tissue -- such as nerve cells in the spinal cord.
The skeptical researchers said, however, the scientists did not offer conclusive evidence the stem cells were a genetic match to the women who donated the initial cells, as they would have to be if cloning truly occurred. They raised the possibility the embryos could have been obtained by other means, including natural processes or even surplus embryos from an in-vitro fertilization clinic.
