AR-News: Human, rabbit DNA combined in embryos

[jim robertson]

Human, rabbit DNA combined in embryos
Journal report fuels debate; some decry work as unethical


Washington Post


Scientists in China have for the first time used cloning techniques to 
create hybrid embryos that contain a mix of DNA from both humans and 
rabbits, according to a report in a scientific journal that has reignited 
the smoldering ethics debate over cloning research.

More than 100 of the hybrids, made by fusing human skin cells with rabbit 
eggs, were allowed to develop in laboratory dishes for several days before 
the scientists destroyed them to retrieve so-called embryonic stem cells 
from their interiors. Although scientists in Massachusetts had previously 
mixed human cells and cow eggs in a similar attempt to make hybrid embryos 
as a source of stem cells, those experiments were not successful.

Researchers said Wednesday that they were hopeful the rabbit work would lead 
to a new and plentiful source of embryonic stem cells for research and, 
eventually, for medical use. But theologians and others decried the work as 
unethical.

Some wondered aloud what, exactly, such a creature would be if it were 
transferred to a womb to develop to term.

The vast majority of the DNA in the embryos is human, with a small 
percentage of genetic material -- called mitochondrial DNA -- contributed by 
the rabbit egg. No one knows if such an embryo could develop into a viable 
fetus, though some experiments with other species suggest it would not.

Congress has been mulling legislation for years that would outlaw certain 
human cloning experiments, with some opposed to any creation of cloned 
embryos for research and others sympathetic to research uses as long as the 
embryos are not allowed to grow into cloned babies. No law has passed, 
however, in part because of researchers' warnings that the proposed 
restrictions are so sweeping that they would hobble development of new 
medical treatments.



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Cruelty to animals is one of the most significant vices of a low and ignoble 
people.
Alexander von Humboldt

In wildness is the preservation of the world. Thoreau

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