Dolly's long goodbye
15th February, 2007
Four years since the death of Dolly the cloned sheep, her legacy very much lives on...
Ten years ago this month the world first heard of Dolly the Sheep - the first mammal cloned from an adult cell. And St. Valentine's Day marked the fourth anniversary of Dolly's "euthansia" at the age of six after a veterinary examination showed she had a progressive lung disease, a condition more common in older sheep.
But this double anniversary doesn't round off the story. Dolly's birth at the Roslin Institute in Scotland marked just the beginning of a long production line of animal clones that has included mice, rats, rabbits, horses, mules, cats and a dog. More ominous perhaps are the cloned cattle, pigs, sheep and goats. For, while Dolly's stuffed remains are to be found exhibited in Edinburgh's Royal Museum, the push is on to serve up the remains of today's cloned livestock on our dinner plates.
Just two months ago a US Food and Drug Administration (FDA)'s draft risk assessment concluded that meat and milk from adult clones and their offspring are as safe to consume as those from standard animals. There has, of course, been no public debate about whether US citizens, let alone the recipients of US exports, wish to consume such fare, and surveys of US public opinion show a decided lack of appetite for cloned food. But we may not have the choice. The FDA has already concluded labelling should not be required while semen brokers have been busy selling thousands of units of semen from cloned bulls. Their offspring are almost certainly going to end up in the food chain. The daughter of a US cloned cow has already been born on a British farm.
The Biotechnology Industry Organization (BIO) sees no need to worry. A clone, claims BIO, is just "a genetic twin of that animal... no genes have been changed or moved or deleted." But clones are far from perfect copies. All clones are defective, in one way or another, with multiple flaws embedded in their genomes. Rudolf Jaenisch, a geneticist at the Massachusetts Institute of Technology, estimates that something like 4-5% of the genes in a cloned animal's genome are expressed incorrectly.
These often subtle genetic defects can have tangible consequences. Cloning produces an extraordinarily high number of deaths and deformed animals. Some clones have been born with incomplete body walls or with abnormalities in their hearts, kidneys or brain function, or have suffered problems like "adult clone sudden death syndrome" and premature ageing. This brings us back to Dolly who developed a potentially debilitating form of arthritis at an unusually early age.
By that point, the company behind Dolly, PPL Therapeutics, had received big public funding guarantees, as Dolly became the biotech icon at the centre of what was supposed to provide Scotland with an emerging "biotech tartan triangle" and a major economic driver. However, in the same year that Dolly died, PPL Therapeutics decided to sell its assets and shut its doors, following multimillion pound losses. It left behind a large herd of unwanted GM sheep in New Zealand that, like Dolly, had to be "euthanised".
But still Dolly lives on, not only in the industry of the abnormal that she gave birth to but as a "cuddly" incarnation of the dream of a world remade without natural boundaries - limited only by our imagination and desires. While the dream may be inherently defective, it has powerful economic drivers. Cloning expert, Peter Shanks, points out that the FDA's favourable draft assessment of cloned food leaned heavily on the work of animal-cloning companies like Cyagra and ViaGen. Over a quarter of the 700-page draft, says Shanks, is a data dump from the two companies - a fact that the New York Times failed to mention, even when quoting the president of ViaGen saying, "I think that this draft is going to provide the industry the comfort it needs."
For Dolly and her "descendants", it looks set to be a long goodbye.
This article first appeared in the Ecologist February 2007.
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