Last week, Britain's Academy of Medical Sciences reported that scientists have created "thousands of examples of transgenic animals" carrying human DNA.
Why have we done this? To save lives...If you can't use people as guinea pigs in gruesome but necessary experiments on human tissue, guinea pigs will do. All you have to do is put -- or grow -- the human tissue in the guinea pigs. You're free to inflict any disease or drug on a human system, as long as that human system lives in an animal.
So far, our mixtures are modest. To make humanized animals really creepy, you'd have to do several things. You'd increase the ratio of human to animal DNA. You'd transplant human cells that spread throughout the body. You'd do it early in embryonic development, so the human cells would shape the animals' architecture, not just blend in. You'd grow the embryos to maturity. And you'd start messing with the brain.
We're doing all of these things.
Neurological disorders affect 1 billion people and kill nearly 7 million per year. To study these disorders, we're doing to brain tissue what we've done to liver and kidney tissue: We're replicating it in animals. We've made humanized mice with Alzheimer's symptoms. We've put human neural stem cells in monkey brains. We've added human stem cells to the brains of fetal mice and grown them into adult mice with human neurons. According to the British academy, it's now standard practice to test human neural stem cells by assessing whether they "integrate appropriately into mouse or rat brain."
When Stanford's ethicists first heard the proposal for humanized mouse brains, they were grossed out. But after thinking it over, they tentatively endorsed the idea and decided that it may not be bad to endow mice with "some aspects of human consciousness or some human cognitive abilities." The British academy and the U.S. National Academy of Sciences have likewise refused to permanently restrict the humanization of animals.
I wrote about the ethical and moral concerns that follow from animal-human hybridization awhile back, and my concerns have not bee assuaged by anything I've read about the issue since then. Now I'm no Luddite, and I'm not going to propose some complete and total ban of animal-human hybrids and experimentation. But I'm not comforted to read that university ethicists are the ones who are decided if this research may or may not be conducted. If Congress can pass rules that govern to what extent we can use stem cells to create human therapies, then Congress has something to say about the extent to which human DNA can be incorporated into animals, whatever the purpose. Which is where we get to the kicker in Saletan's column:
If you want permanent restrictions, your best bet is the senator who tried to impose them two years ago. He's the same presidential candidate now leading the charge against evolution: Sam Brownback, a Kansas Republican. He thinks we're separate from other animals, "unique in the created order." Too bad this wasn't true in the past --and won't be true in the future.
Even a buffoon can be right once in awhile. And Brownback is right to take issue with animal-human hybridization. Unfortunately for me, I can't hop on Brownback's bandwagon as I'm sure that he supports something like a total ban on this type of research (and also, he's a nut.) But it distresses me to no end that to find people who have problems with this, I have to look to the anti-evolution crowd. Surely there are those on my side of the aisle who accept the value and necessity of science and research, but believe that we need to be more carefully considering the implications of this type of research, right?