Chimerically Yours

[Guest David Guyatt]

Is this what may be?

http://www.buzzle.com/editorials/2-28-2005-66375.asp

Animal-Human Hybrids No Longer a Myth

Controversy is erupting over the creation of chimeras—hybrid creatures that are part human, part animal. But the scientists who are conducting such experiments believe the benefits outweigh the ethical dilemma.

Enlarge ImageBy Linda Orlando

It sounds like something out of Jules Verne. In 2003, Chinese scientists at the Shanghai Second Medical University successfully fused human cells with rabbit eggs. The resulting embryos were called chimeras—human-animal hybrids named after a monster in Greek mythology that had a lion’s head, a goat’s body, and a serpent’s tail. These first chimeras ever created were allowed to develop for several days in a laboratory dish before their creators destroyed the embryos to harvest their stem cells.

Human-animal combination isn’t happening just in other countries. In Minnesota last year, researchers at the Mayo Clinic created pigs with human blood flowing through their bodies. And later this year, an experiment is planned at Stanford University in California to create mice with human brains. The reasoning behind such experimentation is that the more humanlike the animal, the better it will perform as a research model for testing drugs, or possibly for growing "spare parts," such as livers, to transplant into humans. And since humans can’t be used as test subjects, the ability to watch human cells mature and interact in a living creature may help scientists in discovering new medical treatments and cures for chronic or terminal illnesses.

But creating human-animal chimeras has raised troubling ethical questions: What types of human-animal combinations should be produced, and why? Should the resulting creature be considered human, and if so, what rights would it be entitled to? Currently, there are no U.S. federal laws that address such questions. However, the National Academy of Sciences, which advises the U.S. government, has been studying both sides of the issue and has plans to release voluntary ethical guidelines for researchers in March of 2005.

Human-Animal Research Is Routine, But Still Troubling

Not all human-animal research studies have been troubling. For example, faulty human heart valves can be replaced with ones taken from cows and pigs. Such surgery essentially makes the recipient—the human—a chimera, but it is widely accepted and routinely performed. And for years scientists have added human genes to bacteria for research purposes, as well as to farm animals to increase favorable characteristics.

The problem with the latest branch of human-animal research studies is due to the mixing of human stem cells with embryonic animals to create whole new species from scratch. Biotechnology activist Jeremy Rifkin does not agree with such intermingling of species; he believes that species boundaries should not be crossed for any reason, even if such studies would lead to medical breakthroughs. "There are other ways to advance medicine and human health besides going out into the strange, brave new world of chimeric animals," Rifkin said, adding that sophisticated computer models can substitute for experimentation on live animals. "One doesn't have to be religious or into animal rights to think this doesn't make sense. It's the scientists who want to do this. They've now gone over the edge into the pathological domain."

According to David Magnus, director of the Stanford Center for Biomedical Ethics at Stanford University, the real concern is whether or not chimeras will be used for procedures that are problematic or risky. As an example, he postulates that mice can be genetically engineered to produce human sperm and eggs, which can then be fertilized in vitro in human beings. Such an experiment would produce a child whose parents are, essentially, a pair of mice. "Most people would find that problematic," Magnus capitulates, "but those uses are bizarre and not, to the best of my knowledge, anything that anybody is remotely contemplating. Most uses of chimeras are actually much more relevant to practical concerns."

Can Government Bans Control Research Effectively?

Last year Canada passed a ban on chimera research, the Assisted Human Reproduction Act. Specifically, it prohibits transferring a nonhuman cell into a human embryo and putting human cells into a nonhuman embryo. Cynthia Cohen, the senior research fellow at Georgetown University's Kennedy Institute of Ethics in Washington, D.C. is also a member of Canada's Stem Cell Oversight Committee, which oversees research protocols to ensure they are in accordance with the new guidelines. Cohen believes a similar ban should be put into place in the U.S. because the creation of chimeras tarnishes the dignity of human beings as a singular species. "It would deny that there is something distinctive and valuable about human beings that ought to be honored and protected," said Cohen. But she believes the wording of such a ban needs to be developed carefully, and should not prohibit ethical and legitimate experiments that could benefit mankind.

The director of Stanford University's Institute of Cancer/Stem Cell Biology and Medicine in California, Irv Weissman, is stridently opposed to the establishment of a ban in the United States. "Anybody who puts their own moral guidance in the way of this biomedical science, where they want to impose their will—not just be part of an argument—if that leads to a ban or moratorium. … they are stopping research that would save human lives."

The outcome of the controversy will have a professional impact on Weissman, because he has already created mice with brains that are about one percent human. Later this year he may conduct a second experiment to create mice with brains that are fully human—by injecting neurons into the brains of embryonic mice. Before they are born, the embryos would be killed and dissected to examine whether a human brain was actually forming, and if the architecture had begun to develop, Weissman would look for traces of human cognitive behavior.

Weissman says he is not a mad scientist trying to create a human in an animal’s body. He hopes the experiment will lead to a better understanding of brain function, which could potentially lead to breakthroughs in treating diseases such as Alzheimer's or multiple sclerosis. His study has not been started yet, because he is awaiting the National Academy’s report.

An Uncertain Future For Chimera Research

The opinions of scientists the world over are divided on the issue. While many believe the creation of chimeras could prove be of profound benefit to the advancement of medical science, many others feel that the problems outweigh the benefits because this is unexplored biological territory. Whatever moral threshold may be set for performing such experiments, there would be considerable risk of exceeding that limit, either by unscrupulous researchers or by scientist who either do not realize they are exceeding the limits or travel into gray areas in the name of science. Although medical scientists have a common goal to advance research into areas that will benefit mankind on the whole, they also have a responsibility to maintain the integrity of both human life and animal life. Research projects that create chimeras run the risk of disturbing fragile ecosystems that have existed for millions of years. While the results of these experiments may lead to advances in medical treatments, they may also endanger the health of the planet on the whole, while creating an affront to species integrity.

Scientists are eagerly awaiting the National Academy of Sciences report, and since the guidelines provided by the report will be voluntary, at least initially, the future is uncertain as to the direction of animal-human hybrid research.

By Buzzle Staff and Agencies

Published: 2/28/2005

[Evan Burton]

Just reference the image:

http://www.snopes.com/photos/arts/family.asp

[Guest David Guyatt]

Just reference the image:

http://www.snopes.com/photos/arts/family.asp

No Evan. I referenced the image aware that it was a sculpture. Hence the rhetorical caption: "Is this what may be?"

Pictures of cuddly mice with human blood flowing through their veins doesn't elevate the subject to the attention level it deserves, imo.

Sometimes shock and horror are required to bring focus on a subject. That was my intention.

Personally, I'm appalled by the prospect of a bunch of unrestrained Dr. Strangelove's mixing the species to satisfy their insane curiosity. It makes Joseph Mengele look rational and balanced.

Am I the only one who thinks this way?

[Evan Burton]

Oh - okay. I misunderstood. Sorry!

I can see the benefits, but the ethical aspects require detailed investigation. IMO, medical science is coming up with new techniques such that transplant parts from animals will no longer be needed in the near future.

[Dave Greer]

I haven't had chance to fully research the bio-technology and it's implications... but for some reason, on a visceral level the whole idea makes me feel squirmingly uncomfortable.

How I balance this up with things like animal experimentation, animal organ transplants, human foetal research, what the heck, let's even throw in eating meat, I don't really know. I just know that from a position of relative ignorance on the subject, it just feels wrong. I may change my mind if there are genuine benefits to be had, but there comes a time when you just have to draw a line in the sand. Is this it?

[Guest David Guyatt]

My sense too, is that this line should definitely not be crossed.

I'm certain we'll be bombarded with all sorts of apparent rational arguments why it will benefit us, but we should always remember what I'll call the "Mengele Paradox"... absolute good when forced to the extremes is absolutely bloody evil.

Let's not forget the abuses that have already occurred in the terrorism laws that have been used in everyday situations (non terrorist in other words) that we were promised would not occur --- but which may of us realized would take place.

As Jung once observed, loaded guns when collected together have a way of going off.

I'm off now to eat a human ear crackling lettuce turtle steak with crispy pork-baby snot foam on a bed of human pigeon toenail ratatouille.

Wish me well. It's a Michelin three star preparation at the famous Pissedon Bloomingpals "Duck Fat".

Yum.