British scientists begin a new study on Tuesday to consider how human DNA is used in animal experiments and to determine what the boundaries of such controversial science might be.
Though experts have been swapping human and animal DNA for years
- like replacing animal genes with human genes or growing human
organs in animals - scientists at the Academy of Medical Sciences
want to make sure the public is aware of what is happening in
laboratories before proceeding further.
"It sounds yucky, but it may be well worth doing if it's going
to lead to a cure for something horrible," said Robin
Lovell-Badge, a stem cell expert at Britain's National Institute
for Medical Research, and a member of the group conducting the
At a media briefing in London, Lovell-Badge said there were two
main types of experiments: altering an animal's genes by adding
human DNA or replacing a specific animal sequence with its human
counterpart. Several years ago, human genes were added to a mouse
to create a model of Down's syndrome for scientists to study how
the disease evolves, which could lead to potential treatments.
Scientists also have tried to grow human organs in animals that
could one day be transplanted back into humans - like a mouse onto
whose back scientists grew a human ear. "There are good reasons
for doing this, but it may upset some people," Lovell-Badge said.
Two years ago, controversy erupted in Britain after scientists
announced plans to create human embryos using empty cow and rabbit
eggs. Critics condemned the mixing of human and animal genetic
material, though scientists said the embryos would be destroyed
after 14 days and would only be used to help them learn how to
create human stem cells.
Scientists said they are now trying to determine where the line
should be drawn on experiments that use human material in animals.
At the moment, the regulation on how much human DNA can be put into
an animal is vague.
"We are trying to work out what is reasonable," said Martin
Bobrow, chairman of the group conducting the study. He and others
said they recognized people might be nervous about experiments
where animals were given human features or brain cells.
David King, director of Human Genetics Alert, an independent
watchdog, said he was not convinced such experiments were
warranted. "This is a classic example of science going too fast,"
he said. "If you cannot firmly say exactly what it is you're
creating, you should not do it."
Copyright 2015 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.