Banning Human-Animal Hybrids

Media Matters has a humorous take on a recent bill introduced by Sam Brownback and Mary Landrieu to ban human-animal hybrids created in laboratories. (Brownback's description of the bill and his reasons for it are here.) The idea that these distinguished Senators would waste all our time protecting the nation from mermaids, centaurs, or whatever other science fiction or fantasy creature their imaginations might conjure, is laughable. Why not an anti-vampire bill? Shouldn't we be protected from the scourge of the undead? And if you vote against it, that just shows you want Dracula to kill America's children, doesn't it?

The problem is not that the bill is a joke, however. The problem is that the bill is not a joke. The bill does have a serious purpose and serious effect. But, as you might expect, a harmful one. The bill is intended to prevent potentially life-saving medical research based on nothing more than religious dogmatism.

Patrick J. Kiger for Discovery Blogs has a description of what this debate is really about.

As it turns out, Bush wasn’t actually envisioning a nightmarish race of what sci-fi writers refer to as parahumans. Instead, he was up in arms about the possibility of scientists combining human genetic material with animal eggs to produce hybrid embryos, which then could be harvested for stem cells — a possible way of getting around political and religious conservatives’ opposition to the harvesting of stem cells from leftover human embryos from fertility clinics. (Back in 2001, Bush essentially barred the federal government from funding such research, unless scientists relied upon a limited number of existing stem cell lines.)

So, part of this ban is supposed to support the already-existing but unwise ban federal funding of embryonic stem cell research (except for a very small number of lines whose utility and genetic diversity are very much in question).

A second, albeit polemical, take on Bush's proposed ban comes from P.Z. Myers' Pharyngula. The important part of this post is the proposal would ban legitimate medical research that has the potential to save and improve lives. So, given the potential medical efficacy of such research, what is the justification for banning it?
Bush's speech included little in the way of justification. (That's a big surprise.)

A hopeful society has institutions of science and medicine that do not cut ethical corners and that recognize the matchless value of every life.

Tonight I ask you to pass legislation to prohibit the most egregious abuses of medical research: human cloning in all its forms; creating or implanting embryos for experiments; creating human-animal hybrids; and buying, selling or patenting human embryos.

Human life is a gift from our creator, and that gift should never be discarded, devalued or put up for sale.

First, he blatantly appeals to emotion. We obviously want to be a hopeful society and apparently that means "recogniz[ing] the matchless value of every life". And that recognition requires banning these hybrids. Let's suppose he means this matchless value only to include human life; otherwise, he would be banning meat-eating. (And let's not even get started on "human cloning in all its forms"--emphasis added.) This is a textbook fallacy in that no attempt is made to connect this appeal to any form of reason for the action. Why doesn't hope require that we fund medical research that can save or improve human lives? Bush provides no answer, so his appeal is fallacious.

Second, Bush relies on an appeal to God. The final sentence is his only real argument: "Human life is a gift from our creator, and that gift should never be discarded, devalued or put up for sale." Do we value every "gift from our creator" in this way? Cancer is at least as much a gift from our creator; does this mean we should ban treatments for cancer? Of course not. He's claiming that human life has infinite (or "matchless") value, and that to create human-animal hybrids in some way devalues that life.

Even this argument makes no sense, however. We don't ban the creation of human life because God gave us this gift or because human life is infinitely valuable. That's completely backwards; if human life is valuable, other things being equal, there should be more of it. So, it must be that, somehow, creating a human-animal hybrid entails that we treat actual humans as having less than infinite value. As noted, this is not the case. If creating these hybrids results in life-saving treatments for disease or genetic disorder (for example), it would seem that creating them evinces great respect and value for human life.

So, we turn to Brownback's arguments. There are basically two arguments here. First,

The issue is that when you make changes in the germ-line, such changes are passed along to one’s offspring. You could make a change now that could be passed along through the gene-pool for the rest of humanity. We do not know what the full effect of this could be, and it could be disastrous.


Tampering with the human germ-line could be the equivalent to setting a time-bomb that might detonate many generations down the line; but once it is set, there is no reversing course.

This is either completely irrelevant or too general a worry to justify the ban. Nothing we know of in the current research suggests that scientists are going to infect humans with a potentially dangerous genetic modification (that won't have any effect until it's somehow spread to all humanity!). That's more like the plot to a science fiction/horror movie. Does he think we're living in a Resident Evil game/movie? In the case of treating Downs' syndrome, even if the treatment resulted in genetic modification of children with it--and finding a treatment by creating an analog syndrome in mice does not make that significantly more likely--it's not likely that the cure would be worse than the disease. And if it were, the cure for that would be to do the research and discover the potential benefits and risks of the treatment. We do not ban all treatments for arthritis because some of them caused heart problems.

That takes us to the seond worry. Perhaps Brownback just wants to warn us about the potential unintended consequences of new treatments which he presents in absurdly apocalyptic terms. If so, such a warning is always salutary, but not particularly relevant to this debate. There's always the possibility of unintended, long-term consequences to any medical treatment. But we don't ban medical treatments for that reason; we require that they be accompanied by long-term studies to determine such potential side effects. We should be especially careful with genetic modifications since the potential side effects might take years or decades to occur, but that just means our long-term studies should be even longer-term. And anyway that issue is completely distinct from the human-animal hybrid issue. If we want to ban human genetic manipulation, ban that. But there's so far no reason to think human-animal hybrids will lead to that in normal humans. We're not turning people into pig-men; we're giving pigs human DNA for medical experimentation, so we don't have to do it to actual humans.

Brownback has one other reason:

Creating human-animal hybrids, which permanently alter the genetic makeup of an organism, will challenge the very definition of what it means to be human and is a violation of human dignity and a grave injustice.

He's not worried about making changes in the DNA of humans; he's worried that giving animals human DNA will make them human, or some kind of sub-human monster, and that creating humans without full-human rights undermines the rights of humans.

Brownback's right that if pigs get X amount of human DNA, then we cannot define humanity by having X amount of human DNA. But there's no reason to define humanity by parts of a human genome. And, going back to first principles, we note that the relevant issue for moral treatment, moral responsibility and rights is not humanity but personhood. So, the worry would have to be that in (for example) creating pigs with bits of human DNA, we will be making a person, or sub-person with some of the rights of persons, which we could then treat as simple property without dignity or rights. If this were the case, it would be reason to worry. But we could easily prevent that at some point if we, for example, needed to create pigs with human intelligence in order to test a treatment for Alzheimer's. But that's not what's happening here. A pig with a little human DNA is no more a person than it was without that DNA. So, again, Brownback's reasoning is totally off the mark.

The only reason he can have here is that he thinks that once something has human DNA, it's human and must have all the rights of a human person. That's obviously false. Humans do not become cold-viruses when they DNA to replicate them. Having some DNA from another species is simply not relevant to one's moral or legal status.

So, what's motivating this? Blind, religious dogmatism. There cannot be reasons behind this for the reasons are so obviously weak or irrelevant. The "reasons" given are a disguise for dogmatic belief in human uniqueness and exceptionalism. Anything that blurs that line or undermines that exceptionalism undermines his religious world-view, so reasons cannot enter the picture. If he really considered the reasons for his bill, he might have to consider reasons for the whole religious edifice. And it's clear that such an edifice would not long stand.