Scientists based at the University of Newcastle have announced the successful creation of human hybrid embryos, made by inserting human genetic material into 'hollowed out' cow eggs. Team leader Lyle Armstrong presented the preliminary data at a conference in Israel. The team hopes that such embryos will eventually be a useful source of embryonic stem cells (ES cells) for research into new therapies for conditions such as Parkinson's disease and stroke.
In January, the Human Fertilisation and Embryology Authority (HFEA) granted two one-year licenses permitting scientists at Kings College London and Newcastle University to create human hybrid (also called human 'admixed') embryos. Both teams aim to use enucleated animal eggs - those from which the nucleus, containing the vast majority of an egg's DNA, has been removed. Genetic material from human patients can be added to these empty eggs, and the resulting embryos used to create ES cells that are virtually human. Currently, scientists studying ES cells have to use human eggs left over from fertility treatment for their research, but these are in short supply and vary in quality.
The hybrid embryos created by the Newcastle team survived for three days, which was not long enough to extract stem cells from them, so much more work remains to be done. Professor John Burn, Head of the Institute of Human Genetics at Newcastle University, said: 'If the team can produce cells which will survive in culture it will open the door to a better understanding of disease processes without having to use precious human eggs. Cells grown using animal eggs cannot be used to treat patients on safety grounds but they will help bring nearer the day when new stem cell therapies are available'.
A survey commissioned by the Catholic Church has found that 67 per cent of the 1,000 people questioned were against plans to create human hybrid embryos. The findings also showed that just over half (51 per cent) strongly opposed the research. Cardinal Keith O'Brien, the leader of the Catholic Church in Scotland, said: 'I am delighted to see that the overwhelming majority of people, like me, are completely opposed to the creation of animal-human hybrids'.
However, the results contradict those from the HFEA's public consultation on hybrid embryos, carried out last year before the authority agreed to license the research. It found that 61 per cent of around 2000 respondents agreed with the use of hybrid embryos for the creation of ES cells, if it might improve understanding of diseases, while a quarter opposed it.