UK Scientists Seek to Create Human-Cow Embryos

NEWCASTLE, UK, November 6, 2006 (ENS) - Stem cell scientists have applied for permission to create embryos by combining human DNA with cow eggs. Their research aims to develop new therapies for human ailments such as strokes, Alzheimer’s and tissue damage suffered by spinal trauma victims. Critics say the mixing of animal and human DNA is unethical and should be illegal.

Dr. Lyle Armstrong, who is based at the North East England Stem Cell Institute at the International Centre for Life in Newcastle, today submitted an application for a three year license from the Human Fertilisation and Embryology Authority, HFEA, for the work.

Stem cells are the body's master cells and each cell has the potential to grow into any type of tissue such as liver, heart and muscle cells.

Scientists eventually hope to take a cell from a patient and re-program it so that stem cells can be extracted to grow new tissue for damaged body parts without fear of immune rejection.


A lecturer with Newcastle University, and a scientist at the International Centre for Life, Dr. Armstrong was a member of the team that created the world’s first cloned human embryo in early 2005. (Photo courtesy Newcastle U.)
Dr. Armstrong and his team of five scientists intend to carry out laboratory tests which involve fusing animal eggs with human cells to try to understand more about how cells are genetically reprogrammed.

Until now, work on the development of therapeutic cloning has used human eggs from consenting patients undergoing in vitro fertilization, but these are in short supply.

Dr. Armstrong said, “At the moment we don’t know if the nuclear transfer process works well enough in humans to create useful embryonic stem cells. We need to carry out many tests to establish this and, as animal eggs are freely available, it makes sense to use these as a source of material for our laboratory work."

"Stem cell research promises huge potential medical advantages and we believe we will be working towards our ultimate goal of developing new patient therapies,” Armstrong said, acknowledging that these therapies could be several decades away.

Teams at Edinburgh University and Kings College London have announced plans to seek permission from the HFEA for similar work. A decision on the NESCI application is expected within the next few months and, once granted, scientists could start work immediately.

If granted, the HFEA licence would allow the scientists to create hybrid embryos that would be 0.1 percent animal and 99.9 percent human, using an established technique known as nuclear transfer, or therapeutic cloning.

The NESCI team would be working with cow eggs. The nuclear transfer technique would involve removing the nucleus of a cow egg - which contains most of its genetic information - and fusing the cow egg with the nucleus of a human cell such as a skin cell.

The egg will then be encouraged to divide until it is a cluster of cells only a few days old called a blastocyst, or an early-stage cloned embryo.

The scientists would attempt to extract stem cells from the blastocyst after six days.


Embryonic stem cell research has been a lightning rod for ethical and moral concerns. (Photo credit unknown)
The quality and the viability of stem cells would then be checked to see if nuclear transfer technique has worked. The scientists would also be observing the way that the cells are reprogrammed after fusion to see if there are useful processes they could replicate in the laboratory.

The embryo would have to be destroyed at 14 days old in accordance with the license.

But critics say the mixing of animal and human DNA is unethical and should be illegal.

The Scottish Council on Human Bioethics, a professional group based in Edinburgh, said in an August report that this type of research raises "grave and complex ethical difficulties."

Calum MacKellar, director of research with the Council said, "The fertilization of animal eggs with human sperm should not continue to be legal in the UK for research purposes."

"Most people are not aware that these kinds of experiments have been taking place in the UK and find it deeply offensive. Parliament should follow France and Germany and prohibit the creation of animal-human hybrid embryos," said MacKellar.

The Council made 16 recommendations, including that it should be illegal to mix animal and human sperm and eggs, or to create an embryo containing cells consisting of both human and animal chromosomes.

The scientists who have applied for permission to conduct this research say there is no possibility of allowing any of the animal hybrid cells to be used to treat patients.

They say their approach will protect resources of human eggs at this early development stage and complement existing NESCI research using human eggs.

The studies will be regulated under the conditions of the HFEA licence. The HFEA would undertake six-monthly audits in the lab to check scientists are complying with its rules, and it would require an annual report on progress.

Dr. Armstrong says This work presents no new ethical problems and is similar to the long established use of animal eggs to test sperm viability.

Dr. Stephen Minger, director of the Stem Cell Biology Laboratory King's College London, also applied to the HFEA for permission to combine cow and human DNA for research at his institution.


Dr. Stephen Minger is director of the Stem Cell Biology Laboratory King's College London. (Photo courtesy King's College London)
"The current state of the technology is such that literally hundreds of human ooctyes [eggs] from young women will be required to generate a single human embryonic stem cell line," Minger told the BBC. "Therefore we consider it more appropriate to use non-human oocytes from livestock as a surrogate."

"We feel that the development of disease-specific human embryonic stem cell lines from individuals suffering from genetic forms of neurodegenerative disorders will stimulate both basic research and the development of new medicines to treat these horrific brain diseases," said Minger, an American working in Britain for the past 10 years.

Dr. Armstrong said, “We are very hopeful that the HFEA will grant us permission for this work, which will help us to understand more about how cells behave after the nuclear transfer process. We need this information to enable us to take this area of stem cell research to the next stage."