- Melding man and beast may sound like the stuff of science
fiction, but it's not.
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- Amid all the advances in genetic manipulation, the idea
of combining the DNA of animals and humans has gone beyond the talking
stage -- it's been attempted.
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- Indeed, many scientists and academics are wondering how
far it might go and what the ethical implications would be. If a human
were crossed with a chimpanzee, for example, would it still be human? And
if not, then what would it be?
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- The first publicized case of animal-human hybrids took
place in 1996 when Jose Cibelli, a scientist at the University of Massachusetts,
took DNA from his white blood cells by swabbing the inside of his cheek.
He then inserted the DNA sample into a hollowed-out cow egg.
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- Cibelli's experiment came to an end after a week of growing
the cell mass, he told scientists earlier this month at a panel meeting
of the National Academy of Sciences in Washington, D.C.
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- This raised the question of what might have emerged had
the cell mass continued to develop.
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- "As far as we know, it would still look like a human
being, but some of the characteristics of individual cells might be slightly
different," said James Cross, a molecular biologist at the University
of Calgary who attended the meeting.
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- If such an embryo could develop, he said, the result
would resemble a human being but carry bovine mitochondria, the energy-producing
component of every cell. This is because the cow's egg shell, or cytoplasm,
contains genetic materials known as mitochondrial DNA.
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- "This suggests that we can create new human-animal
species," said Jeremy Rifkin, biotechnology critic and president of
the Washington-based Foundation on Economic Trends.
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- Rifkin called the experiment "the most extraordinary
single development in the history of biotechnology."
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- Such experiments have become public only when the makers
of hybrids, who fund their operations through investor capital, apply to
patent their inventions.
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- In partnership with Massachusetts-based Advanced Cell
Technology, Cibelli came out from under a shroud of secrecy in 1998 when
the firm applied to patent the alleged invention.
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- Last October, Greenpeace Germany dug up a patent claim
for a similar human-animal hybrid, only this time it involved a pig. U.S.-based
Biotransplant and Australia-based Stem Cell Sciences grew a pig-human embryo
to 32 cells before ending its life.
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- "If the embryo had lived, it would be 95% human,"
said Michael Khoo, a genetic engineering campaigner for Greenpeace's Toronto
branch. "The possibilities are not only frightening, but it's unknown
just how many other similar patent applications are out there."
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- Meanwhile, critics and futurists are having a field day
speculating on the future of biotechnology.
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- "Chimpanzees share between 95% and 98% of our genes,
so the prospect of creating a human-chimpanzee hybrid are highly probable,"
Rifkin said. "The question becomes: What percentage of human genes
will it take before human rights kick in? Would a hybrid have to look and
talk like a human before it can get human rights?"
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- While the concept of making and owning such a creation
for 20 years under patent law is controversial to say the least, the science
behind combining animal eggs and human DNA could be useful, said Cross.
"In the case of Dolly, it took 277 eggs to get the sheep. In normal
IVF programs, the number of eggs you get usually ranges between five and
10. So, to solve a potential shortage, some scientists have considered
using an egg from a different species to house human DNA."
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- While such an attempt to improve the egg supply may be
scientifically possible, people are not ready for such a brave new world
which involves crossing the species barrier, said Diane Cox, who chairs
the medical genetics department at the University of Alberta. "Right
now, technology is way ahead of ethics. The Canadian population is worried
enough about relatively trivial things, let alone such a bizarre concept."
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