Britain's Human Fertilisation and Embryology Authority (HFEA) gave the go-ahead to controversial plans to merge human cells with eggs from animals such as cattle.
Scientists argue such research could pave the way for therapies for diseases like Parkinson's and Alzheimer's.
HFEA decided to accept such research, which involves placing human DNA into cow or rabbit eggs that have had their genetic material removed. According to the ruling, projects would be decided on a case-by-case basis, said Paula Woodward, a spokeswoman for the regulator.
People “at ease” with idea
An HFEA consultation found that people were "at ease" with the proposals once the possible implications had been explained.
"It does seem a little abhorrent at first analysis, but you have to understand we are using very, very little information from the cow in order to do this reprogramming idea," said Dr Lyle Armstrong, of Newcastle University, according to the BBC.
"It's not our intention to create any bizarre cow-human hybrid, we want to use those cells to understand how to make human stem cells better."
Embryos will be mostly human
The research involves transferring nuclei containing DNA from human cells to animal eggs that have had nearly all their genetic information removed.
The resulting embryos are therefore mostly human, with a small animal component.
Stem cells, which can grow into different kinds of tissue, are then formed.
The embryos could give researchers a large supply of stem cells to work with. Presently they have to rely on human eggs left over from fertility treatment, which are in short supply and often of poor quality. – (Sapa)
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