You don’t need to be an arachnologist to know that spiders are capable of spinning incredibly strong and flexible webs. They do so using something called “spider silk,” a protein fiber. Wikipedia notes that spider silk has a tensile strength “comparable to that of high grade steel” but is arguably even better due to its extensibility — some types of spider silk can “stretch up to five times their relaxed length without breaking.”
The science community wants to harness that power for humanity, unsurprisingly. But farming silk from spiders isn’t easy (if even possible), and in any event, it isn’t a very cost-effective way of getting the material. So researchers have had to get creative. Which is where Freckles comes in.
Freckles is a goat.
Or, more accurately — and importantly for these purposes — Freckles is a goat which happens to be part-spider. Dr. Randy Lewis (no relation), a researcher at Utah State University, is the reason why. Dr. Lewis works at something called the Synthetic Biomanufacturing Institute at Utah State and focuses his research on how to harness spider silk. His method: find other organisms, combine their DNA with that of spider DNA, and cultivate the silk from that genetically-modified organism. Freckles is one of his experiments.
As Dr. Lewis explained to the Guardian, Freckles was, literally, designed to express spider silk in her milk — from before birth:
[Dr. Lewis] and his team took the gene that encodes dragline silk from an orb-weaver spider and placed it among the DNA that prompts milk production in the udders. This genetic circuit was then inserted in an egg and implanted into a mother goat. Now, when Freckles lactates, her milk is full of spider-silk protein.
After Freckles is milked, Lewis and team are able to extract the strands of spider silk they’re after. And the possibilities for its use are extensive:
With a glass rod, we delicately lift out a single fibre of what is very obviously spider silk and spool it on to a reel. It has amazing, and desirable, properties, which is why Randy’s seemingly bizarre research is so robustly funded. “In the medical field, we already know that we can produce spider silk that’s good enough to be used in ligament repair,” he tells [the Guardian reporter]. “We already know we can make it strong enough as an elastic. We’ve done some studies that show that you can put it in the body and you don’t get inflammation and get ill. We hope within a couple of years that we’re going to be testing to see exactly the best designs and the best materials we can make from it.”
While neat and promising, spider goats aren’t likely to become popular any time soon, though. Boiling off the milk is a fast way to get to the protein, but not in the silk structure we need it to be in to be viable. And while we can fish out individual fibers of silk from the milk, as noted above, that extraction process is still too cumbersome, expensive, and nowhere near commercially viable. So for now, we have to stick to steel — and regular, non-spidery goats.
From the Archives: Google’s Lawn Mowing Goats: Another alternative use for goats.