Researchers in the UK have requested permission to generate embryos by inserting human nuclei into cow eggs that have been depleted of their own nuclei. These embryos, which would not be allowed to develop for longer than 14 days, would be used for stem-cell research aimed at treating neurological disorders such as Alzheimer's and Parkinson's disease. Another team of researchers wants to use a similar technique to study how eggs can reprogramme adult cells into stem cells (BBC News, 7 Nov 2006).

“We are concerned that the current state of the technology means that hundreds of eggs from young woman will be required to generate a single human embryonic stem cell line. Therefore, we consider it more appropriate to use non-human eggs from livestock as a surrogate”, says Stephen Minger, one of the researchers (Telegraph, 7 Nov 2006).

Although not an entirely new technique, mixing human and animal eggs and sperm is prohibited in the UK by the Human Fertilisation and Embryology Act 1990. But, the applicants are hopeful that this could change within a few months, opening up a new range of research possibilities.

Unsurprisingly, some members of the public are critical. Calum MacKellar of the Scottish Council on Human Bioethics is concerned that these studies “might also undermine human dignity and human rights” (BBC News, 7 Nov 2006).

However, Evan Harris, a member of parliament and a member of the Commons Science and Technology Select Committee, raises an opposing point: “If human benefits can be derived by perfecting therapeutic cloning techniques or from research into subsequently-derived stem cells, then it would actually be immoral to prevent it just because of a 'yuck' factor” (BBC News, 7 Nov 2006).