Carl Zimmer in his excellent blog, The Loom:
In the standard Frankenstein story, a scientist creates an unnatural monster that breaks out of the lab and runs amok. But why should unnatural make something unstoppable? The contrary is possible, too. Imagine a different story: Frankenstein’s monster escapes, realizes that it can’t survive in the outside world, and retreats back to the lab. This story line may not make for a satisfying movie, but it might be a good goal for real life.
The fear of the unstoppable unnatural has been with us ever since scientists began moving genes between species in the 1970s. In a 1973 experiment, researchers transferred a gene from a frog into Escherichia coli. The gut microbe used the frog gene to make a frog protein.
It wasn’t long before researchers figured out how to use genetic engineering to turn microbes into factories. When scientists inserted the gene for human insulin into E. coli, the bacteria were able to manufacture a drug that had previously been harvested from cow pancreases. E. coli became the workhorse of biotechnology, spewing out drugs, vitamins, and industrial materials. (For more on E. coli’s strange yet significant history, see my bookMicrocosm.)
At first, the prospect of foreign genes in E. coli was terrifying. Some critics warned that insulin-producing bacteria would escape from fermenting tanks, get into people’s bodies, and cause an epidemic of diabetic comas. That never happened, probably because insulin does E. coli no good at all. The human gene is a burden to the microbe, draining off energy and resources it could use to grow.