Human cloning: scientific progress and ethical concerns

13 October 2011

Researchers have created partially patient-specific human embryonic stem (HES) cells by cloning.
Growing human embryos from adult patients is a key goal for many who are trying to develop stem cell therapeutics, as stem cell lines derived from such embryos would be a perfect match for the adults and could be used to treat various diseases. It was reported to have been achieved by South Korean scientist Hwang Woo-Suk, but this work was later discredited (see previous news).
In the latest publication, researchers successfully produced early human embryos by fusing adult skin cell nuclei with donor egg cells. They found that leaving the donor egg cell genetic material in place allowed the resulting cloned embryo to develop to the blastocyst stage – much further than when the donor genetic material was removed, as in previous techniques, and enough to give rise to stem cell lines.
Although the resulting embryos contained too many chromosomes (three sets instead of two) and would not be usable as a source of cells for therapy, the scientists say that, ‘with a reliable source of human oocytes’ it should prove possible to generate stem cells with the correct levels of genetic material.

Comment: Whilst technically interesting, this work raises significant ethical concerns, since the large number of human egg cells (oocytes) it used were procured by paying women donors. Ethical guidelines typically oppose any form of financial inducement for egg donation, which carries health risks for women, and concerns over ethical probity in obtaining human eggs were the first problem to beset the South Korean laboratory (see previous news). However, the scientists said that since women in the US could receive $8000 for egg donation for reproductive purposes, offering the same fee was essential to secure the eggs they wanted. 

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