According to George Q. Daley of the Children's Hospital Boston Stem Cell Program, one of the researchers who led the analysis, Hwang and his team "unwittingly" created the world's first human embryonic stem cell apparently due to some mistakes during the tedious nuclear transfer technique.
"They were, however, unable to detect parthenogenesis because of lack of tools," he said. "We know now that the Koreans' first supposed nuclear transfer-derived stem cell line was actually derived from the woman's egg alone."
Parthenogenesis is the growth and development of an embryo without fertilization by a male. It occurs naturally in some species, including lower plants, invertebrates and some reptiles.
Daley noted that although the discovery would not obviate the need to create embryonic stem cells through nuclear transfer, it would land an important tool in the hands of scientists to create cell lines with less tissue compatibility issues.


