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Can Centaurs and Talking Pigs Be Far Behind?

The United Kingdom Department of Health reverses its proposed ban on chimeras, saying that Parliament should allow the fusing of humans and other species.

Nobel laureate and famed geneticist Sydney Brenner once delivered a somewhat tongue-in-cheek lecture to students at Cambridge University about how to nonsurgically create a centaur. He concluded that one day soon it might be possible to create such a six-limbed vertebrate. Mermaids and other mythical hybrids might be on the way, too, as well as human-dog drudges trained to cook omelets and happily perform useful tasks around the house, like changing the light bulbs.

This day has not yet arrived, but it may be inching closer with a recent amendment to a bill in the British Parliament that would legalize human hybrids for research. This legislation, offered by the British Department of Health, is a U-turn from government ministers who said last December that they supported a ban on creating chimeras.

Since then, a vigorous and sometimes contentious debate has raged in the United Kingdom between supporters of a ban–some religious, some not–and the scientific community, led by Ian Wilmut (Dolly the sheep) and others who insist that a ban would stifle research into stem-cell treatments. On March 28, a lengthy report by the Science and Technology Committee in the House of Commons endorsed chimerical research as part of the legislation reauthorizing the Human Fertilization and Embryology Act of 1990.

Wilmut and the other United Kingdom scientists are not interested in making mermaids–or mermen, either. They want to use animal eggs to grow human stem cells by cleaning out 99.9 percent of the animal materials from the eggs and injecting them with human DNA. These hybrids would provide a solution to the severe shortage of pure human eggs needed for embryonic stem-cell research, which now depends on human volunteers to provide eggs.

Advocates of outlawing chimeras (the “no to mermaids” bunch) were predictably outraged. Here is what the GuardianUnlimited website said recently about the pro-banners:

There were only 300 responses to the government consultation, with 277 opposed to the research–although many of these came from pro-life groups opposed to any research on embryos. But not all opposition is religious or ethical. Some scientists are also sceptical about the research. Josephine Qunitavalle, of the lobby group Comment on Reproductive Ethics, told the Guardian: “One has to ask, what will they actually create? It is simplistic or even deceptive to say they are simply making stem cells. In order to obtain stem cells. They … have to create a ‘something’ from which to derive the new cells. What is this something? It must be in some way human to be of any use to researchers.”

Some scientists were also upset by the way the measure has been handled. Currently, the chimera clause is an addendum and not part of the main bill. The entire embryo package still needs to be discussed and voted on by the Science and Technology Committee, and then it must go through the approval process in the full House. Scientists also consider the legislation’s cumbersome licensing process for approving hybrid research to be overly restrictive for this fast-moving science.

Two groups in the United Kingdom–at King’s College London and at Newcastle University–have already applied for licenses to create embryos by injecting human cells into empty eggs from rabbits or cows. Their applications are on hold, pending the fate of the legislation. (See the GuardianUnlimited article “Human-Animal Embryos Get Go-Ahead.”)

On our side of the pond, chimeras are not even on the table at the federal level: Washington remains locked in a pointless debate over whether to allow embryonic stem-cell research at all.

This gridlock has led to a ridiculous state of affairs in which our country has failed to have a meaningful debate about chimeras. Some states have allowed scientists to race ahead with this science, which may yield promising treatments, but it also has a potential to produce monsters.

In 2003, Panayiotis Zavos created “human cow” embryos that lived for several days and, theoretically, could have been implanted into a woman’s womb. Researchers at the Mayo Clinic in Minnesota have produced pigs with hybrid pig-human blood cells. Last year, Yale researcher Eugene Redmond injected millions of human neural stem cells into the brains of monkeys afflicted with Parkinson’s disease.

The inability of the Bush Administration and many leaders in Congress to accept the reality of stem-cell science over the past few years is creating another dangerous situation in which our body politic has not had the sort of political debate and argument that the United Kingdom is now having over hybrids.

As my friend Greg Stock says, hybrids are inevitable. But before we start making centaurs and such, we should pause and talk about the possibility in a rational manner, taking a cue from the Old Country.

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