The human-animal hybrid embryo is formed from an animal egg cell (most likely from cows or rabbits). Scientists want to use such embryos to create genetically human embryonic stem (ES) cells. This method would overcome difficulties associated with the collection of human eggs from donors, and would provide a much more fruitful source of embryos for scientists.This egg cell's nuclear DNA is removed and replaced with nuclear DNA from an adult human. The cell is then 'kick-started' - with a small electric shock - into commencing cell division. The embryo would be almost 100 per cent human - the only non-human DNA in the cell comes as part of the cell's mitochondria: apparatus for providing the cell with energy.
Currently, the vast majority of human eggs given by donors are for IVF treatment and not for research. A recent consultation by the HFEA entitled 'Donating Eggs for Research: Safeguarding Donors' stressed both the ethical and safety concerns associated with methods used to collect human eggs. The creation of human-animal hybrid embryos is safe in that it involves no human participant, except for the collection of a few skin cells. The voices arguing against the work are few; indeed there has been a distinct lack of comment pieces in the press supporting a potential ban. Naysayers rely on two arguments: a moral argument, and the prediction that this avenue of research will be useless. The practise of creating human-animal hybrid embryos is, they say, unnatural, and therefore immoral. This is a familiar reaction to new biological technology: IVF is 'unnatural', but is now accepted as a useful technology to aid fertility treatment. And although no one yet knows whether this research will prove fruitful, this should not be used as argument for banning the work. The proper action should be to let the research commence, and to monitor the results for potential benefits, or ethical concerns.
Two important points must be brought to the attention of the public:
1) The enormous potential that this avenue of research could hold. The 'could' should also be stressed. Nothing tangible has resulted from this work at this stage, but scientists agree that this line of research should not be closed before its potential fruits can be assessed.
2) The fact that there is absolutely no likelihood that this work could result in a 'hybrid-human' or any other 'Frankenstein's monster' type result. The subject of the research is cells, not animals. These embryos are a potentially useful research tool, and the potential for exploring new avenues of research should be welcomed.
The Roman Catholic Bishops of England (RCBE) have told the UK parliament that inter-species embryos - those containing genetic information from both human and animals - should not be treated any differently from 'normal' embryos, and that women should be given the chance to carry their genetic offspring to term.
There is currently a real shortage of human eggs for use in embryonic stem (ES) cell research. It is hoped the problem can be overcome through creating embryos by transferring human genetic material into 'hollowed out' animal eggs. The resulting entity - a 'cybrid' - would be over 99 per cent genetically human and less than one per cent animal. As it stands, the new draft Human Tissue and Embryos Bill in the UK will ban the creation of embryos that contain genetic material from both animals and humans, but will make an exception for certain types of research, including cybrid embryos. The draft Bill imposes a strict 14 day time limit on the use of these entities in research, at which point they must be destroyed.
The RCBE and the Linacre Centre for Healthcare Ethics told the parliamentary committee who are scrutinising the draft Bill: 'At the very least, embryos with a preponderance of human genes should be assumed to be embryonic human beings, and should be treated accordingly. In particular, it should not be a crime to transfer them, or other human embryos, to the body of the women providing the ovum, in cases where a human ovum has been used to create them'.
The RCBE have been accused of misunderstanding the science involved in creating such embryos. Cybrid embryos will have no 'mother'; rather, an animal ovum will be stripped of its genetic identity and used as an empty vessel to cultivate hES cells from cloned human cells. It is hoped that such research will lead to advances in treatment for devastating diseases such as Parkinson's and Alzheimer's.
Liberal Democrat MP, Dr Evan Harris, has described the RCBE's position as 'absurd' and 'inconsistent', adding: 'Most of these embryos will be created using animal eggs, but even if they were created using human eggs, they would be created by cloning and the Catholic Church has previously opposed reproductive cloning of even fully human embryos'.
