Digital Information in DNA Strands

In the Middles Ages, a majority of Greek and Roman texts were lost. But in large monasteries, monks dutifully hand copied texts in rooms called scriptoriums. Working in silence, they preserved works, which may have otherwise been lost.

According to Robert Grass, of ETH Zürich, the monks were preserving information for future generations. In a digital age, the question facing modern society is how to preserve intangible information.

“Most of us don’t have photographs, or real photographs of the pictures we take. We don’t have paper copies of the work we perform. Everything is online and digital,” Grass said at the 250th National Meeting & Exposition of the American Chemical Society (ACS).

Grass and colleagues have addressed this problem by demonstrating information encapsulated in the form of DNA can be preserved for at least 2,000 years.

DNA, according to Grass, is a logical route of storage due to its track record storing information over hundreds of thousands of years. In 2013, National Geographic reported scientists sequenced a genome from the leg bone of a 700,000-year-old horse.

“We take this idea of storing information in DNA,” Grass said. “We know that it is extremely stable, if it’s stored correctly, over hundreds of thousands of years. And we then have to think, ‘Well, how do we not store genomic information, but digital information?’”  

“More or less, you go from translating something which is a sequence of 0s and 1s to…a sequence of A, C, T and Gs,” he added.

According to ACS, a hard drive the size of a paperback book can store five terabytes of information, and last 50 years. But, in theory, a fraction of an ounce of DNA is capable of storing more than 300,000 terabytes.

Using silica glass, “We chemically entrap DNA molecules, and in that entrapped state they are almost as stable as they are when they are entrapped in fossil(s),” said Grass.

According to ETH Zürich, the researchers encoded DNA with text from Switzerland’s Federal Charter of 1291, and “The Methods of Mechanical Theorems” by Archimedes.

Afterwards, the silica spheres were subjected to temperatures of 160 F for one week, meant to simulate storage of 2,000 years at 50 F. The sample was error-free when decoded, Grass said. The team implemented data redundancy in their storage technology to correct any errors during the decoding stage.

“Right now, we can read everything that’s in that (DNA) drop,” said Grass. “But I can’t point to a specific place within the drop and read only one file.” Making the DNA storage searchable is the next task for the team.

But don’t expect to see this technology any time soon. According to Grass, storing a few megabytes costs thousands of dollars. It’s certainly one of the biggest constraints in this field, in any academic or new technology field, he said.