In an effort to free stem-cell research from its dependence on donated human eggs, medical researchers in the UK have applied for permission to implant human DNA into cows eggs, effectively creating a human-bovine hybrid.
Researchers from Newcastle University and Kings College, London, have applied to the Human Fertilisation and Embryology Authority for a three-year licence, the BBC reports. They want to implant human DNA into bovine oocytes, or eggs, whose nuclei have been removed.
The resulting embryo, technically a hybrid of the two species, or a chimera, would then be grown for a few days, before the stem cells would be harvested and the embryo destroyed.
The idea is that researchers could refine therapeutic cloning techniques using these hybrid embryos.
Unsurprisingly, the plan has its critics, but its supporters say vital stem cell research should not be held up because of a "yuck factor".
Just how much of a yuck factor the proposals present depends on how much information you have. The statement "scientists propose human-cow hybrid" is pretty "yucky". But the suggestion that scientists should use the "shells" of cows eggs to hold human DNA for a few days, is somehow less so.
The proposal raises some serious ethical questions, nonetheless. In particular, Calum MacKellar, from the Scottish Council on Human Bioethics, warns that the research could blur the human/animal divide.
He said: "In this kind of procedure, you are mixing at a very intimate level animal eggs and human chromosomes, and you may begin to undermine the whole distinction between humans and animals."
The problem is that stem cell research is still at a very early stage. Scientists say literally hundreds of human eggs, which have to be harvested from volunteers in a painful and invasive procedure, are neccessary to create a single successful stem cell line.
They argue that using animals aggs to conduct this early stage research is a rational step, and would allow the research to progress much more quickly.
Professor Robin Lovell-Badge, head of developmental genetics, National Institute for Medical Research, argues that researchers should learn as much as possible from "readily obtainable" animal eggs before moving on to using the much more valuable human oocytes.
Dr Stephen Minger, from King's College London, added: "We feel that the development of disease-specific human embryonic stem cell lines from individuals suffering from genetic forms of neurodegenerative disorders will stimulate both basic research and the development of new medicines to treat these horrific brain diseases."
Stem cell research has the potential, scientists say, the develop treatments for diseases such as Parkinson's and Alzheimer's. ®