- LONDON (AP) - British scientists have
created a frog embryo without a head, a technique that may lead to the
production of headless human clones to grow organs and tissue for transplant,
The Sunday Times reported.
- None of the embryos grown by scientists
at Bath University were allowed to live longer than a week, the newspaper
reported in its early edition Saturday.
- But the scientists believe the technique
could be adapted to grow human organs such as hearts, kidneys, and livers
in an embryonic sac living in an artificial womb.
- Many scientists believe human cloning
is inevitable following the birth of the sheep Dolly, the world's first
cloned mammal, at a laboratory in Scotland. Scientists at The Roslin Institute
in Edinburgh created Dolly using cells from the udder of a dead sheep.
- The Sunday Times said the two techniques
could be combined so that people needing transplants could have organs
"grown to order'' from their own cloned cells.
- The genetic composition of grown organs
would exactly match those of the patient, eliminating the threat of rejection.
It would also ease the shortage of organs for transplant.
- Growing partial embryos to cultivate
customized organs could bypass legal restrictions and ethical concerns,
because without a brain or central nervous system, the organisms may not
technically qualify as embryos.
- "Instead of growing an intact embryo,
you could genetically reprogram the embryo to suppress growth in all the
parts of the body except the bits you want, plus a heart and blood circulation,''
said embryologist Jonathan Slack, professor at Bath University.
- Some scientists accuse Slack of meddling
- "It's scientific fascism because
we would be creating other beings whose very existence would be to serve
the dominant group,'' Oxford University animal ethicist Professor Andrew
- "It is morally regressive to create
a mutant form of life,'' he said.
- But Lewis Wolpert, professor at University
College London, said Slack's suggestions did not raise ethical issues "because
you are not doing any harm to anyone.''
- Headless frog embryos can be created
with relative ease by manipulating certain genes, suppressing development
of a tadpole's head, trunk and tail.
- Slack believes the breakthrough could
be applied to human embryos because the same genes perform similar functions
in both frogs and humans.
- Under current government rules, Slack's
embryos are not considered animals until they are a week-old, when they
have to be destroyed.