The Chimera Dilemma Manifested in Sheep

Rollie Hawk writes "While many limits on stem cell research exist in the United States, scientist are finding wants to straddle or at least blur the line between man and animal. It's not quite The Island of Doctor Moreau, but it's bringing a pantheon of ethical dilemmas, nonetheless. The creation of chimeras, named for the mythical beast composed of parts from several different animals, has been in the news off and on for the last few months. The latest case involves around 50 sheep said to possess at least partially human organs. These heavily modded sheep are growning human-like organs such as livers, hearts, and blood. All of these could eventually be close enough to the real thing to be harvested as replacements parts. If that doesn't shock you, consider one other human organ that is being grown in some of these sheep: human brains. While it is doubtful that anyone would want a brain transplant from a human-sheep chimera, it does hold the possibility for doing brain research that would never be allowed on human beings. That is, unless, the brains end up being too human. Just the possibility of a human mind bouncing around inside a sheep's head is a scary proposition."

Comments

Bioethics

[geomon]

Two researchers were discussing this topic on Science Friday last week.

The thing that kept running through my mind as I listened to the discussion was how someone with enough money could run circles around these ethics panels and produce chimeras off-shore.

Now that Bush has made the political (rather than scientific) decision to limit stem cell lines, this activity will most certainly occur outside of the US and beyond any jurisdiction of American ethics organizations.

Re:Bioethics

[sas-dot]

NewYork times had a detailed sunday magazine article on Apr 10 . (now you have to pay to read this) The article included about the politics among scientists behind this research. I quote few of them below, including the most bizzare possiblity!

..For several years, Brivanlou, a 45-year-old developmental biologist at Rockefeller University in New York, has been arguing that one of the best ways to understand the usefulness of stem cells for regenerative medicine is to first insert them in an animal embryo and see how they divide and differentiate in a living system. The experiment is explicitly prohibited by the institutions that supply the stem-cell lines approved by the Bush administration, so he is using private funds to develop his own lines. He plans to insert them into 3-to-5-day-old mouse embryos, which he will then implant in the wombs of female mice. Brivanlou is anxiously awaiting the publication of the National Academy of Sciences guidelines before proceeding, but he says he doubts that they will prove an impediment. In his view, showing the potency of stem cells only in a petri dish is like testing the power of a new car by revving its engine in the garage. He wants to take the car out on the track and see how it might perform some day on the open road.

....
Robert Lanza, vice president for medical and scientific development at Advanced Cell Technology in Worcester, Mass., says much the same thing. ''I personally don't want to engage in those kinds of experiments, and I won't have any of my scientists do that work,'' he says. ''Sure, we could reach our endpoints quicker that way. But it takes you into very murky water.''

Why all the shuddering? For starters, there is the gonad quandary. If the experiment really works, the human cells should differentiate into all of the embryo's cell lineages, including the one that eventually forms the animal's reproductive cells. If the mouse were male, some of its sperm might thus be human, and if it were female, some of its eggs might be human eggs. If two such creatures were to mate, there would be a chance that a human embryo could be conceived and begin to grow in a mouse uterus -- a sort of Stuart Little scenario, but in reverse and not so cute.

''Literally nobody wants to see an experiment where two mice that have eggs and sperm of human origin have the opportunity to mate and produce human offspring,'' says Dr. Norman Fost, professor of pediatrics and director of the bioethics program at the University of Wisconsin and a member of the National Academy of Sciences committee reviewing stem-cell research policies. ''That's beyond anybody's wildest nightmare.''

Is the concern over the reproductive issue overblown? It is, of course, biologically impossible for a human fetus to be delivered from a rodent uterus. Moreover, for a human embryo to be conceived, the chimeras would have to be born first in order to mate, and Brivanlou says he has no intention of allowing them to come to term. He plans to terminate them and examine the fate of the human cells after a week. Still, there remains the question of what kind of being would be present during those seven days. Nobody knows. Does even the fleeting, prenatal existence of a chimera of unknown aspect cross a moral line -- not because of what it might look like or become but simply for what it is?

That's *COOL*

[fazil]

Human brains in sheep? Now that's just plain *COOL* Hacking the genes.. loads of fun!

I don't know why so many people get upset about this kind of thing.. I mean, if my mom had something like CJD from eating euro-beef 10 years ago, and you could sacrifice a legion of humo-sheep hybrid brains to save her.. Sacrifice away! Myself, I have a damaged heart.. if I could have a new one, I'd kill any number of chimera sheep to get it. I want to watch my boy grow up, not die at 35. Oh, and you go tell that hypotetical burn victim why he'll be deformed for the rest of his life, because he can't have the artificial skin developed from chimera sheep in Qwai Pong Province china, because his narrow minded government doesn't think it's ethical.

In the balance of life, they're sheep. Who cares? Grow them in vats for all I care. As long as this is all done in a clean room environment, so we can minimize the risk of having superbug's crossing the sheep human barrier...

Uhhh

[quantaman]

the committee recommended closely monitoring the mice's behavior and immediately killing any that display human-like behavior.

You know when considering a solution to that particular ethical dilemma that wasn't the first idea that came to mind...

Re:"Heavily modded sheep"

[Rei]

What the article *doesn't* mention is that if you poke the sheep enough, they'll explode on you.

On a more serious note, was anyone else distrubed by the fact that it was recommended, concerning human-brained mice, that they monitor for signs of humanlike behavior in human-brained mice, and if they find such behavior, they were to... immediately kill the mice? Excuse me? If a mouse is starting to think like a person, shouldn't the appropriate response be to cease testing, ensure a good life for it, and only euthanize it if there are signs that it is suffering?

Re:I know!

[ZephyrXero]

Could possibly go in the "Your Rights" section too. All those people who were afraid of genetic stuff aren't sounding quite as crazy now...

Go back to writing about run-away brides

[John Newman]

Every once in a while you read a story that seems to have been written by a science writer with at least a quarter of a clue, and then you find that one fateful line that reaffirms the proper order of things: that science writers are complete idiots who have no business writing about science:

First, human stem cells were injected into bacteria, then mice and now sheep.

We inject human stem cells into single-celled prokaryotes that are probably less than one-thousandth the volume of a stem cell? I'd like to see that trick. The writer presumably confused human stem cells with human DNA, and probably wouldn't know the difference if it were pointed out to him/her, anyway.

I despair of scientific literacy in this country.

Re:Oryx and Crake

[Adelbert]

This is way too close to Margaret Atwood's Oryx and Crake for comfort

Actually, I was thinking that this was really close to the bit in "The Restaurant At The End Of The Universe" Where the cow tells Arthur that it looks forward to being eaten. Surely this is all this new tech is building up to?

Re:Bird brain

[X0563511]

Hmm... next step after geting a human like brain is to instigate Alztimers (spelling? im lazy) and see if we can figure out how to stop it, and, probably impossible, but reverse it.

Re:what happens when they show human behaviour?

[MidnightBrewer]

Okay, just because you have human brain cells does not automatically make the brain capable of human intelligence. First of all, human brain cells taken as individual neurons are by no means superior to any other animals. Second of all, this is definitely a case of "it's the size that counts." Not only does the brain's structure play a role in how the brain works, but its size matters, too. A brain that is too small is going to simply lack the critical mass to develop past a certain level of intelligence. Finally, it's like pouring water into a container: the water takes on the form of whatever it's in. So whereas there's a remote possibility that the sheep might be smarter than average (and that's assuming a lot), the sensory inputs to teach the brain are completely wrong; it will be a human brain that thinks it's a sheep.

Let's put it this way: how do you know you're not a sheep's brain trapped in a human body?

Mengele

[Ironsides]

If the reason we're holding back scientific progress is actually "ethics"-- people complaining about genetics and such keep using that word, I am not sure they know what it means

Hmm... complaining about medical eithcs. So are you a supporter of Josef Mengele by any chance? Or any of his ilk?

The main reason most people seem to be against this is, at what point is the chimera no longer an animal? At what point does it qualify as human or sentient? Doing this blurs the line and that is what they are afraid of.

Re:I agree completely

[Fwonkas]

Ok, maybe I'm in the minority here, but I don't eat chicken mcnuggets. ;)

That aside, while I see the validity and importance of most of your points, I think you're setting up a bit of a strawman argument here. Nuclear weapons programs are often implemented to ensure that other nations can't intimidate them with their nuclear arsenals. It's unpleasant, but at this time there are not many other options. I believe that's part of the reason for the so-called "Star Wars" program(s), as much as I question their usefulness.

More importantly, you question the ethics of the opposition to this research. You're brushing off their concerns by saying, "give them legal rights and a social security card". The concern is that when you start to muddy up the distinctions between human and animal, it's less clear what sort of things are ethical. One wouldn't remove a healthy human's heart without their consent. If a sheep is part or mostly human, is it ok to remove their heart for transplant? That is an ethical question. Once it becomes ok to remove a quasi-human sheep's heart, how far a leap is it to remove a human's heart?

That's totally disregarding the question of whether we're justified in doing these sorts of things to non-human animals capable of suffering anyway.

I agree with some of your sentiment overall, and I think this sort of research can benefit humanity tremendously, but I just wanted to point these things out. I think it's unfair to characterize objections as being due to just "grossout factor(s)".

Re:I agree completely

[Goldenfool]

You've raised several issues that should be addressed. First I want to agree with what you've said, your thinking is very much in line with my own. Science has been used to create an uncountable number of terrors that we have unleashed upon this world: the nuclear bomb, anthrax, computer viruses that can bring entire corporations to a standstill, and let's not forget Fear Factor.

Science has also brought about a great deal of wonderful advances as well. Americans today throw away more food than ever before in the history of the world. We can get places faster and pollute our atmosphere and water with constantly increasing efficiency. And though we have the medicine and technology to allow people to live decades longer than they would have just a century ago, we see thousands of deaths every year from the excess consumption of Chicken McNuggets.

Don't get me wrong, I think technology is a good thing. I just think that people need ot deal with it responsibly. Engineering a human liver in a sheep for instance, is not inherently wrong. The ethical argument against it is one of the legitimacy of "playing god." If you look at the most ubiquitious traits of "god" or any other divine figure, the defining characteristic is usually the ability to create and destroy up to a cosmic scale. Biblically speaking, man was created in the image of God. That does not just mean that we have bodies that look like his/hers/its. We, like God, have the ability to create and destroy.

So the ethical question is "is it right to create a sheep with human organs?" I personally have no problem with this, and have trouble finding a theological basis for saying that God (or whathaveyou) would dislike this new "shuman" (or maybe just "heep) any less than any other creation on this planet. Just remember, we've been selectively breeding dogs for centuries for hunting, companionship, or even entertainment. Manipulating DNA is just the next step in selective breeding.

One (or maybe more, I forget) of your responders brought up the issue of what happens on a social level when sheep become more human than sheep. What happens is if we deem them to be close enough to human, we will give them "human rights." We would not kill a human being to harvest their organs (in theory), so we would extend the same courtesy to the sheep. If they become sentient, who knows, maybe they'll get to vote. That's what happened when we finally realized that black people and women were sentient. Social definitions are constantly in flux and are extremely elastic. I see no reason why they would not be able to shift to accommodiate sentient species other than humans.

Finally is the "gross-out" factor you speak of. To those who say that it is wrong to create sheep with human livers because it is gross and unnatural, I say "keep away from them, then." We hear the same sentiments towards lesbian/gay/bisexual/transgendered individuals. We're not saying that because they offend people they should not exist (at least, those of us with common sense and human decency don't). We say that if you're uncomfortable with people who live with that lifestyle, just don't bother them and they won't bother you. There was the same sort of social uproar 50 years ago when people tried to marry inter-racially or inter-faith. We are facing the definition of social acceptability and progress. I could go on about this, but I imagine most people haven't even bothered to read this far. To sum up, I agree with your point of view, I just felt it needed some exploration.