Posted on 07/02/2003 4:30:19 PM PDT by aculeus
An experiment that led to the deliberate creation of a hermaphrodite human embryo was condemned as irresponsible by fertility scientists yesterday.
The chimera - named after the Greek monster that was part lion, part serpent and part goat - was formed by placing cells from a newly-conceived male embryo into a three-day-old female embryo.
The resulting embryo was part male, part female and could potentially have developed into an apparently healthy foetus.
The American fertility doctor behind the experiment claimed the creation of chimeras could eventually be used to treat genetic diseases.
But mainstream scientists said the research was pointless and could endanger the reputation of serious embryo research.
Chimeras can occur naturally when twin embryos fuse in the womb a few days after conception. The resulting babies contain genetic material from both embryos. If the embryos are different sexes, the babies will resemble boys but have characteristics of both sexes.
In the past, researchers have created animal chimeras including a goat-sheep. But the creation of human chimeras is illegal in Britain.
The research is yet another challenge to conventional reproduction. Just as the development of clones raised the possibility of children with just one genetic parent, a chimera created by merging two unrelated embryos could have four. Details of the experiment were presented at the European Society for Human Reproduction and Embryology in Madrid by Dr Norbert Gleicher, the head of a private American fertility clinic.
Dr Gleicher and colleagues took cells from three-day-old male embryos and inserted them into 21 female embryos at the same stage of development.
Three days after conception, embryos consist of around eight primitive stem cells from which the entire human body and placenta derive.
Male cells, carrying the Y sex chromosome, were used to allow the team easily to track the distribution of the donor cells in the developing embryo. After three days, the male appeared to be evenly distributed in 12 of the chimeras, he told the conference. The embryos were destroyed soon after.
Dr Gleicher said chimeras could help treat genetic diseases such as severe combined immunodeficiency.
"Scid" babies are born with no immune system as a result of a single gene mutation. The condition can be treated with a bone marrow transplant in which healthy donor stem cells are given to the baby.
But Dr Gleicher hopes that one day, parents could use cells from healthy embryos to pass on healthy genes to siblings with the defective gene.
Repairing faulty embryos in vitro would increase the number of embryos available for use in IVF treatment, he said.
"If you have a defective embryo and you are able to introduce just 15 per cent healthy cells, you may be able at that point to treat single gene disorders," he said.
"Normally you would do this with embryos of the same sex but we did it with different ones as a model. Our primary purpose was to see if this was feasible and I think we have convincing evidence that the answer is yes." The research has been submitted to the journal Fertility and Sterility. The embryos had been donated for use in research, he said.
"I would agree that currently to consider this kind of experiment would be wrong. But now we believe transplants are possible, we could think about experiments in animal models," he added.
Prof Lynn Fraser, a fertility specialist of King's College London, questioned the point of the experiments and whether chimeras could ever be used to treat single gene disorders. "It's a non-starter. Biologically it's an unsound approach," she said.
"He is talking about putting good and bad cells together at an early stage and there's no way you can guarantee that the good cells would get to the organ system affected by the bad gene.
"I don't see how it could be of use in the treatment of single gene disorders."
Prof Alan Trounson of Monash IVF clinic, Melbourne, Australia, one of the pioneers of IVF treatment and stem cell research, said: "It doesn't make any sense to me. It seems completely flawed."
Looks like the herms could have a good lawsuit against David Derbyshire and his employer for the article HEADLINE.
And that is just the start. The Moreau concept is not new, but it will be reality in our lifetimes. And even if it is banned here -- cheap "soldiers" for the 3rd world. Imagine somebody like Saddam, with a few billion to spend, building a self breeding army of high IQ language speaking dobermans and pit bulls. Baboons that can take orders and fire AK-47s, and have no concerns about eating the population they are supposed to terrorize into following the police state directives.
The "Terminator" concept is crap. No one who knows anything about software is going to buy that one. But genetically enhanced animals? Snip, snip. A little DNA here, a little there. It won't happen fast...but it WILL happen.
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