29 Aug 2013

Exploring genetic manipulation of animals

We’ve always felt free to meddle with animals in the name of good breeding, with results that sometimes backfire. We have Dalmatians that are prone to deafness, retrievers with weak hind legs, pugs and bulldogs that can barely breathe.


But as Emily Anthes shows in her witty and well-researched new book, “Frankenstein’s Cat: Cuddling Up to Biotech’s Brave New Beasts,” the rise of biotechnology has taken animal manipulation to an entirely new level. And the results can vary from the beneficial to the profitable to the absurd.

To start with the beneficial, who could argue with a cheap and easy remedy for diarrhea, which takes the lives of two million children a year? Researchers at the University of California, Davis, have developed a genetically modified goat whose milk contains lysozyme, a bacteria-fighting substance found in human breast milk. But the Food and Drug Administration, asked in 2011, has yet to rule on its safety.

On the other hand, GloFish, the world’s first genetically modified pet, got quick FDA approval in 2004. You can buy a zebra fish in “six striking colors,” including “Starfire Red” and “Galactic Purple” (though not in California, which has banned sales).

Anthes views this state of affairs with dismay. “Ironically, it’s the makers of useful transgenic animals that are struggling to get the official stamp of approval,” she writes. “GloFish sailed through because they were totally trivial.”

Then there is cloning, which at first glance seems both profitable and silly. After the announcement in 1996 that a sheep had been cloned from a mammary-gland cell — hence her name, Dolly, as in Parton — scientists and entrepreneurs raced to duplicate the feat with other species.

The Missyplicity Project, for example, was financed with $3.7m from a then anonymous donor to clone a friend’s beloved border-collie mix, Missy (her clones were born 10 years after her death from preserved tissue).

A spinoff company, Genetic Savings & Clone, cloned a cat named Rainbow; her kitten, CC, was born in 2001, and the company was swamped with requests for the $50,000 procedure.

In an example of the cuteness and punning that afflict the cloning business, CC stands for carbon copy. Anthes patiently explains that this is a misnomer: clones have the same genes, but they are not all expressed identically.

Despite her scientific expertise, Anthes can’t resist playful perkiness herself. On somatic-cell nuclear transfer, the technique used to clone Dolly and others: “The procedure is not unlike removing the custard from the middle of a Boston cream doughnut and refilling the doughnut with jelly,” she writes. In the next paragraph, she describes “the turkey-baster-like tool called a pipette” and “an electric current that turned the membranes of both cells into Swiss cheese.”

Cloning does have beneficial possibilities, and Anthes discusses them thoughtfully. Endangered or extinct species could be cloned. If we had taken cells from cheetahs when they were still abundant, we could examine them for genetic variants that have disappeared from the wild, she writes, adding, “We could clone these animals back into existence, and set them free on the African savanna, restoring genetic lineages that had died out.”

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