These Plastic Bunnies Got a DNA Upgrade. Next up, the World?

The bunny became a training ground for a generation of computer graphics designers. They learned how to layer textures and render fur over its leporine curves. It was smashed and fractured and melted in service of advancing their animation skills. It became so iconic that to this day, almost anyone learning to use a 3D printer starts out by making a plastic version of the same rabbit.

So in a way, Erlich’s bunny is the ultimate inside joke. “Plus, you know, you pull rabbits out of the hat,” he says. A computational biologist-slash-white-hat hacker, Erlich gained notoriety in the mid-2000s for using a well-placed cell phone to break into a major Israeli bank. A few years later, he unmasked the identities of people listed in an anonymous genetic database, using only an internet connection. Then, last year, he showed that such databases have grown so big, it’s now possible to find more than half the US population, even people who’ve never taken a DNA test.

He first hatched the idea for DNA-infused objects with his brother in-law, a graphic designer. They were talking about how to make photos—real ones, the kind you put in frames and albums—hold up over time. It made him think: Maybe it would be possible to convert a jpeg file into DNA and spray it on the photo itself, a finishing step to give it digital replicability.

But DNA is a fragile molecule. High temperatures, strong pH swings, and UV light all cause it to deteriorate, degrading the information it encodes. Preserving its chemical structure is key to any DNA data storage dreams.

Erlich emailed Grass, the guy who’d pioneered a method to trap DNA molecules inside a tiny protective glass shell. In 2013, he had figured out how to create silica particles with a positive electrical charge, making them stick to negatively charged DNA. They’d form a thin film that could protect the molecule from a number of threats.

Using that technology, the pair designed a process for producing materials with their own DNA memory, just like the cells in your own body. It involves first converting the digital blueprint of an object into a genetic sequence, producing the corresponding molecules of DNA, encasing them in silica, embedding the beads in melted plastic, spinning that plastic into filaments, loading those filaments into a 3D printer and then printing the object. Easy! They describe the work in today’s issue of Nature Biotechnology.

Just as it’s theoretically possible to take a few cells from your body and make another copy of you as a clone, you can snip a little piece off Erlich’s rabbit and use it to make others. The one he carries around, in fact, is a third-generation clone. The data file Grass’s team used to 3D-print it was retrieved from a tiny piece of ear from a bunny that had come from a tiny piece of an ear of the first bunny they made. They dissolved away the plastic and glass from the ear fragment, converted the remaining DNA back into a digital file, and uploaded the file to a 3D printer. All together, the scientists made five generations of bunnies with no information loss between manufacturing cycles. The bunnies, and the digital files that described them, remained identical over many months.

“This is a very initial foray into one of the more promising applications of DNA data storage: ubiquitous storage,” says Sriram Kosuri, a biochemist at UCLA who was not involved in the work. With ubiquitous storage, all everyday objects could be tagged with useful information, such as where they were manufactured, their ingredients or composition, instruction manuals, safety warnings, and recommendations for how best to recycle or dispose of the item. “What’s cool about this work is they show that it is doable today, and it seems pretty reliable,” says Kosuri.

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