The FDA has approved only one product, ATryn, an anticoagulant derived from the milk of transgenic goats.

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Nexia became known as the spider-silk company, after it created transgenic goats capable of producing spider silk (which is, in fact, a form of protein) in their milk.

ECONOMIST: REPORTS

Since transgenic goats, for example, are living factories whose worth depends on their producing as much milk as possible, every measure is taken to keep them happy, healthy, well fed and sequestered from non-transgenic animals.

ECONOMIST: REPORTS

It's a model that scientists have tried with spider silk before, but because the proteins in spider silk are so large, it takes some pretty wacky-sounding techniques to replicate them (like getting it from the milk of transgenic goats).

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