Hwang Cloned Stem Cells
By Kim Tae-gyu
Staff Reporter
Korea??s top experts on unisexual reproductions claim the country??s disgraced scientist Hwang Woo-suk indeed created cloned human embryonic stem cells.
Prof. Seo Jeong-sun at Seoul National University (SNU), arguably the country??s most authoritative expert at the unisexual reproduction, Wednesday made the claims after checking tests by Hwang??s men.
``The so-called No. 1 stem cell batch featured via Science in 2004 seems to be a cloned one, which is severely damaged or mutated,???? Seo said.
His remark negates suspicions that Hwang and his crew created the No. 1 line through parthenogenesis, or reproduction without a father.
After delving into the veracity of Hwang??s research, a peer-review SNU panel raised such a possibility this January based on a DNA fingerprinting test with the No. 1 cell line.
The test showed that just 40 of total 48 polymorphism markers of the No. 1 line correspond with those of a somatic cell donor. For the cloned cells, all the 48 markers should be identical.
The investigators?? idea was that an unfertilized egg might grow to an embryo by accident, thus spawning stem cells at issue, instead of being established through cloning.
Seo also thought there is a high likelihood that the mysterious cell line was harvested via the unisexual reproduction but changed his mind after confirming another experiment, called imprinting analysis.
The analysis was conducted by Hwang??s underlings including Prof. Kang Sung-keun at SNU and was presented to The Korea Times and Prof. Seo.
``The analysis, which I believe is legitimate, says the No. 1 cell line has imprinted genes that came from both its father (somatic cell) and mother (egg). That means that the cells cannot be created as a result of parthenogenesis,???? Seo said.
``Then, the cells should be cloned ones. The discrepancy of eight markers appear to be triggered by severe impairment or genetic alteration at a process of nurturing them,???? he added.
As far as parthenogenesis is concerned, Seo is one of the global leading biologists. Alongside Japanese associates, he produced a pair of mice in 2004 by combining two eggs, breaking a deep-seated belief that mammals cannot be born with only maternal genes.
SNU Prof. Lim Jeong-mook, another of the country??s handful of researchers at parthenogenesis, concurs. He worked with Hwang in animal cloning from 1997 to 2000.
``Tests are proving the No. 1 line was an indeed cloned one. There is little possibility that the cells in question are extracted via the unisexual reproduction,???? Lim said.
``Despite the data fabrication scandal he was involved in, we need to recognize Hwang??s feats of cloning human embryonic stem cells. They are breakthrough achievements,???? he claimed.
The cloned cells are expected to open the door to a revolutionary cell therapy, which will help treat several hard-to-cure diseases like Alzheimer??s and diabetes without causing immune responses.
By stark contrast, Seo flatly downplays the significance of Hwang??s works even after acknowledging Hwang did extract cloned human embryonic stem cells.
``First and foremost, Hwang faked data and that is indisputably the most significant point. We should not forget it while trying to figure out the identity of the No. 1 line,???? he said.
``In addition, the No. 1 line would be of little use for experiments or applications for therapy because it was damaged too severely,???? Seo contended.
Source: http://times.hankooki.com/lpage/200603/ ... 910220.htm
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