by Playfuls Staff |
7th November 2006
Researchers are seeking legal approval to create embryos that are part-human, part-animal. They consider the resulting hybrid embryo as an aid to develop cures for serious diseases.
[more]
Two separate teams have submitted applications to the Human Fertilisation and Embryology Authority to be permitted to conduct experiments in which human cells will be fused with animal cells, specifically, rabbit, cow and goat eggs. By doing this, the researchers will be able to create early-stage embryos that would be 99.9 per cent human and 0.1 per cent animal in order to produce embryonic stem cells — the body's basic building blocks that can grow into all other types of cells.
It has been proven already by Chinese scientists that stem cells can be harvested from embryos created by fusing human cells with rabbit or cow eggs. Therapeutic cloning has been possible so far through the use of human eggs from consenting IVF patients (in vitro fertilization), but these are in short supply.
Prof Robin Lovell-Badge, of the National Institute for Medical Research, said: "This is a very rational step: to learn what you can using animal eggs, which are readily obtainable, before moving on to valuable human eggs when or if this becomes necessary."
If the researchers are granted permission to carry on with their experiments, the resulting embryos, of mixed human and animal origin, would be destroyed at a very early stage of development, before becoming “more”.
Dr Stephen Minger's group at King's College, London, want to use the cloned hybrid embryos to create embryonic stem cells carrying the defects responsible for conditions such as spinal muscular dystrophy, Parkinson's and Alzheimer's. Dr Minger said: "We are concerned that the current state of the technology means that hundreds of eggs from young women will be required to generate a single human embryonic stem cell line. Therefore we consider it more appropriate to use non-human eggs from livestock as a surrogate to generate these disease-specific cell lines until the efficiency of this procedure is improved."
However, the scientists’ request has attracted strong reactions, the plans being called “abhorrent”. Opponents claim these experiments would undermine "the whole distinction between animals and humans". Calum MacKellar, from the Scottish Council on Human Bioethics, said, "In the history of humankind, animals and human species have been separated. In this kind of procedure, you are mixing at a very intimate level animal eggs and human chromosomes, and you may begin to undermine the whole distinction between humans and animals."
One does wonder, how about freak accidents?
The Human Fertilisation and Embryology Act 1990 makes it illegal to mix human and animal eggs and sperm. There is an exception though, in what is called the "hamster test", by which fertility doctors test the quality of human sperm by fertilizing a hamster egg and then destroying it no later than the two-cell stage. Once again, we wouldn’t want any freak accidents…
The Human Fertilization and Embryology Authority (HFEA) has reportedly consulted lawyers on whether it has the power to approve yesterday's applications.
Dr Minger said that when it came to implanting human cells into animal eggs there was a "regulatory void". He added: "Part of the reason we are doing this is to get some sort of clarification."
Dr Lyle Armstrong and five colleagues at the North East England Stem Cell Institute in Newcastle want to insert human skin cells into cow eggs to study how eggs can reprogramme adult tissues into more primitive cells. Their eventual aim is to develop a way of creating stem cells that could be used to grow new tissue — such as liver, heart and muscle cells — that genetically matches individual patients. This could then be transplanted without the risk of it being rejected by the immune system.
Josephine Quintavalle, the director of Comment on Reproductive Ethics, said: "This is abhorrent. It sounds like the craziest kind of science imaginable. There is a basic human feeling that animals and humans do not mix in these areas. I think the public will be very upset by this because it makes people feel uncomfortable."
Researchers claim the resultant embryo would be 99.9 percent human. And we do believe they are well-intended and passionate about their work, about saving lives. But aren’t the lines becoming too blurry?
A decision will be announced after three months. In the meantime, the HFEA will thoroughly inspect the lab work.
