British team makes mixed human animal embryos

Embryos containing both human and animal material have been created in Britain for the first time, a month before the House of Commons is to vote on new laws to regulate the controversial research.

A team at the University of Newcastle-upon-Tyne announced tonight that it had successfully generated “admixed embryos” by adding human DNA to empty cow eggs, in the first experiment of its kind in the UK.

The achievement will heighten debate over the ethics of human-animal embryos, as the Commons prepares to debate the Human Fertilisation and Embryology Bill next month.

Admixed embryos are widely supported by the scientific community and patient groups, as they provide an opportunity to produce powerful stem cell models for investigating diseases such as Parkinson’s and diabetes, and for developing new drugs.

Their creation, however, has been vociferously opposed by religious groups, particularly the Roman Catholic church. Cardinal Keith O’Brien, the head of the Catholic church in Scotland, described the work last month as “experiments of Frankenstein proportion”.

The admixed embryos created by the Newcastle group are of a kind known as cytoplasmic hybrids or “cybrids”, which are made by placing the nucleus from a human cell into an animal egg that has had its nucleus removed. The genetic material in the resulting embryos is 99.9 per cent human.

TNewcastle cybrids lived for three days and that the largest grew to contain 32 cells. The ultimate aim is to grow these for six days and then to extract embryonic stem cells for use in research---with diseased human cells.
The resulting stem cells could be used as models of those diseases to provide insights into their progress and to test new treatments.

It is already illegal to culture human-animal embryos for more than 14 days or to implant them in the womb of a woman or animal and these prohibitions will remain in the new legislation.