RESEARCHERS in the region have been celebrating after regulators decided "in principle" to allow human-animal embryos to be created.

It is hoped the controversial new research could eventually lead to cures for a range of difficult to treat conditions such as Parkinson's Disease and Muscular Dystrophy.

Dr Lyle Armstrong, of the Institute for Human Genetics, Newcastle, said; "This is excellent news. It is a positive outcome, not just for our work, but for the progress of British science in general. We hope that this will lead to new technologies to benefit everyone."

The dream of researchers is that one day they will understand how to produce stem cells on demand. These cells, which have the ability to become different types of human tissue, can only be produced by manipulating embryos and could be used to treat patients.

The Newcastle University scientists want to use cow eggs as part of this process, because human eggs are in short supply.

Although the North-East team will have to wait until November for a definite go-ahead, yesterday's decision by the Human Fertilisation and Embryology Authority (HFEA) means the region looks likely to become one the world's leaders in the field of stem cell research.

Two years ago, scientists at the university succeeded in cloning Britain's first human embryos.

They removed the genetic material from a human egg cell and replaced it with a patient's genetic material, using a technique called nuclear transfer.

The cell was then electrically stimulated and made to divide into stem cells, which have the potential to develop into almost every type of human cell, including nerve, heart and pancreatic cells.

The theory, which has already worked with animals, is that these cells can be injected back into a sick patient, replacing cells that have degenerated.

The new research will involve scientists removing the genetic material from cows' eggs and injecting a nucleus of human cells into the egg.

The resulting material will be 99.9 per cent human and 0.1 per cent animal.

The HFEA came to its decision after public consultation showed that most people appeared to be ready to approve such experiments.

The decision paves the way for the 20-strong team of scientists, based at the Institute of Human Genetics at Newcastle's Centre for Life, to create what would be the world's first human-animal embryos.

Dr Armstrong, the stem cell scientist who heads the Newcastle University team with his wife, Dr Majlinda Lako, said: "We have been using animal species to establish the principle behind this technique. Now we can make that last jump to using human cells."

But not everyone is convinced that the research is wise.

Dr Robert Song, who teaches Christian ethics at Durham University, said there was a danger of regarding the resultant embryos as objects.

"If you believe, as I do, that human embryos should be regarded as human beings, then I think you are going to find this profoundly problematic."