Kulapavana Posted December 2, 2004 Report Share Posted December 2, 2004 Source: Washington Post Published: November 29, 2004 Author: Rick Weiss 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 that 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." Chimeras (ky-MIR-uz) - 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 borne. 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. In experiments like those, Greely told the academy last month, "there is a nontrivial risk of conferring some significant aspects of humanity" on the animal. Greely and his colleagues did not conclude that such experiments should never be done. Indeed, he and many other philosophers have been wrestling with the question of why so many people believe it is wrong to breach the species barrier. Does the repugnance reflect an understanding of an important natural law? Or is it just another cultural bias, like the once widespread rejection of interracial marriage? 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 that 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?" Unfortunately, said Harvard political philosopher Michael Sandel, speaking last fall at a meeting of the President's Council on Bioethics, such protections are unlikely. "Chances are we would make them perform menial jobs or dangerous jobs," Sandel said. "That would be an objection." The potential power of chimeras as research tools became clear about a decade ago in a series of dramatic experiments by Evan Balaban, now at McGill University in Montreal. Balaban took small sections of brain from developing quails and transplanted them into the developing brains of chickens. The resulting chickens exhibited vocal trills and head bobs unique to quails, proving that the transplanted parts of the brain contained the neural circuitry for quail calls. It also offered astonishing proof that complex behaviors could be transferred across species. No one has proposed similar experiments between, say, humans and apes. But the discovery of human embryonic stem cells in 1998 allowed researchers to envision related experiments that might reveal a lot about how embryos grow. The cells, found in five-day-old human embryos, multiply prolifically and - unlike adult cells - have the potential to turn into any of the body's 200 or so cell types. Scientists hope to cultivate them in laboratory dishes and grow replacement tissues for patients. But with those applications years away, the cells are gaining in popularity for basic research. The most radical experiment, still not conducted, would be to inject human stem cells into an animal embryo and then transfer that chimeric embryo into an animal's womb. Scientists suspect the proliferating human cells would spread throughout the animal embryo as it matured into a fetus and integrate themselves into every organ. Such "humanized" animals could have countless uses. They would almost certainly provide better ways to test a new drug's efficacy and toxicity, for example, than the ordinary mice typically used today. But few scientists are eager to do that experiment. The risk, they say, is that some human cells will find their way to the developing testes or ovaries, where they might grow into human sperm and eggs. If two such chimeras - say, mice - were to mate, a human embryo might form, trapped in a mouse. Not everyone agrees that this would be a terrible result. "What would be so dreadful?" asked Ann McLaren, a renowned developmental biologist at the University of Cambridge in England. After all, she said, no human embryo could develop successfully in a mouse womb. It would simply die, she told the academy. No harm done. But others disagree - if only out of fear of a public backlash. "Certainly you'd get a negative response from people to have a human embryo trying to grow in the wrong place," said Cynthia Cohen, a senior research fellow at Georgetown University's Kennedy Institute of Ethics and a member of Canada's Stem Cell Oversight Committee, which supported a ban on such experiments there. 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theist Posted December 2, 2004 Report Share Posted December 2, 2004 Real prajapatis due their work as assigned to them by higher authority. These scientists are like monkey's let loose to play in the lab in comparison. Of course their intelligence greatly exceeds mine so what am I to them? But such misguided intelligence will lead to disaster. "Chances are we would make them perform menial jobs or dangerous jobs," Sandel said. "That would be an objection." Without doubt this all leads to the creation of a slave class. They will be owned by the same corporations that put up the money that backed the scientific work. Archer Daniels Midland will sub-contract Genentech to produce a 100,000 farm laborers to work their fields. Weird semi-human's mixed with the best qualities from the animal kingdom to do a certain work. Strong backs mixed with a tolerance for the sun etc. Oh man it is getting weirder and weirder. But then again what should we expect. It's like somebody is changing the channels on us from Father Knows Best to the Sci-Fi Channel's showing of Far Beyond the Island of Dr. Moreau. This reminds me, I recently cut off my sattelite service so no more TV for me. I feel better already. Quote Link to comment Share on other sites More sharing options...
Kulapavana Posted December 3, 2004 Author Report Share Posted December 3, 2004 some of the GE work allows my diabetic daughter to live using bacteria produced "human" insulin and not the pig produced substitute derived from slaughtered animals. I take this to be progress any day. yet, the risks are very real. am I worried? not really. ultimately Krishna controls the whole show. if a super lethal "bug" created by GE wipes out the human race - they certainly had it coming.... Quote Link to comment Share on other sites More sharing options...
theist Posted December 3, 2004 Report Share Posted December 3, 2004 Funny you would mention GE. In 1972 GE via their employee Ananda Chakrabarty applied for a patent on a bacterium. Obviously he didn't creat the bacteria he just manipulated already existing organisms. At first the patent was denied. On appeals it went to the US Supreme Court and they eventual won the patent rights in 1980. The Supreme Court ruled in a 5-4 decision that there is no legal distinction between the living and the nonliving. So the legal groundwork is laid for the ownership of geneticly manipulated living beings. I got this from the book Who Are You by Chris Butler aka Siddhasvarupa. Great book by the way. I am not sure if they still are in print. He has a whole chapter on the case in the back of the book. The ramifications are huge as we are seeing in the news daily. Think about that again, no legal distinction between the living and the nonliving. Quote Link to comment Share on other sites More sharing options...
Kulapavana Posted December 3, 2004 Author Report Share Posted December 3, 2004 actually I used GE to mean "genetically engineered" /images/graemlins/smile.gif Quote Link to comment Share on other sites More sharing options...
theist Posted December 4, 2004 Report Share Posted December 4, 2004 The less code the better for me. I am easily confused. Yes they will always be able to show some ways that they have improved somethings but overall it will beused as a tool for eugenics and creating a slave class I think. Quote Link to comment Share on other sites More sharing options...
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