Friday, November 26, 2004

Will "Self" One Day Be A Spare Part? Chimeras & You

This excerpt is from a larger article in the Washington Post this week. It raises a lot of interesting ethical issues, of course. The most interesting of which is focused on growing spare human parts inside animals. These chimeras could produce a vast array of human giblets. . .livers, kidneys, hearts. Won't this lead to raising vast herds of animals/chimeras for transplantable organs? Is that so bad? Is it worse than raising vast herds of animals for hamburgers? If you keep creating these hybrids, and, say, making them more and more human, with several human parts inside, and what point do they become Humanzees, or Hu-hogs? Is there a Maginot Line between humans and animals that cannot, or should not, be crossed? Even if there is, should we be fiddling with this like Victor Frankenstein? The Maginot Line, after all, was thought of as impenetrable as the Titanic was unsinkable...

We've already cloned sheep. It didn't work out all that well, so far anyhow. Folks are trying to clone humans at this very moment. If we put human brains in the right animals, things could start to get really interesting. Gorilla infantrymen? A Giraffe as President of the United States? Doberman security guards? Chimpanzee strawberry pickers? Whales as one-man submarines??
/jack

Scientists debate creation of hybrids of animals, humans
By Rick Weiss, The Washington Post Nov. 2004

WASHINGTON - In Minnesota, pigs are being born with human blood in their veins. In Nevada, there are sheep whose livers and hearts are largely human.

In California, mice peer from their cages with human brain cells firing inside their skulls.

These are not outcasts from "The Island of Dr. Moreau," the 1896 novel by H.G. Wells in which a rogue doctor develops creatures that are part animal and part human. They are real creations of real scientists, stretching the boundaries of stem cell research.

Biologists call these hybrid animals chimeras, after the mythical Greek creature with a lion's head, a goat's body and a serpent's tail. They are the products of experiments in which human stem cells were added to developing animal fetuses.

Chimeras are allowing scientists to watch, for the first time, how nascent human cells and organs mature and interact - not in the cold isolation of laboratory dishes but inside the bodies of living creatures. Some are already revealing deep secrets of human biology and pointing the way toward new medical treatments.

But with no federal guidelines in place, an awkward question hovers above the work: How human must a chimera be before more stringent research rules should kick in?

The National Academy of Sciences, which advises the federal government, has been studying the issue and hopes to make recommendations by February. Yet the range of opinions it has received so far suggests reaching consensus may be difficult.

During one recent meeting, scientists disagreed on such basic issues as whether it would be unethical for a human embryo to begin its development in an animal's womb, and whether a mouse would be better or worse off with a brain made of human neurons.

"This is an area where we really need to come to a reasonable consensus," said James Battey, chairman of the National Institutes of Health's Stem Cell Task Force. "We need to establish some kind of guidelines as to what the scientific community ought to do and ought not to do."
How human?

Chimeras (ki-MER-ahs) - meaning mixtures of two or more individuals in a single body - are not inherently unnatural. Most twins carry at least a few cells from the sibling with whom they shared a womb, and most mothers carry in their blood at least a few cells from each child they have born.

Recipients of organ transplants are also chimeras, as are the many people whose defective heart valves have been replaced with those from pigs or cows. And scientists for years have added human genes to bacteria and even to farm animals - feats of genetic engineering that allow those critters to make human proteins such as insulin for use as medicines.

"Chimeras are not as strange and alien as at first blush they seem," said Henry Greely, a law professor and ethicist at Stanford University who has reviewed proposals to create human-mouse chimeras there.

But chimerism becomes a more sensitive topic when it involves growing entire human organs inside animals. And it becomes especially sensitive when it deals in brain cells, the building blocks of the organ credited with making humans human.

Greely and many other philosophers have been wrestling with the question of why so many people believe it is wrong to breach the species barrier. Many turn to the Bible's repeated invocation that animals should multiply "after their kind" as evidence that such experiments are wrong. Others, however, have concluded the core problem is not necessarily the creation of chimeras, but rather the way they are likely to be treated.

Imagine, said Robert Streiffer, a professor of philosophy and bioethics at the University of Wisconsin, a human-chimpanzee chimera endowed with speech and an enhanced potential to learn - what some have called a "humanzee."

"There's a knee-jerk reaction that enhancing the moral status of an animal is bad," Streiffer said. "But if you did it, and you gave it the protections it deserves, how could the animal complain?"
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