Scientists Store Video Clip in DNA of Living Cells
This first could lead to health-monitoring molecular recorders inside cells
Throughout human history, people have come up with all sorts of data storage systems—from cuneiform and chiseled inscriptions to hard drives and compact discs. But they all have one thing in common: At some point, they degrade.
That’s why researchers have been on a quest to find more durable data storage, like diamonds and even DNA. Now for the first time, reports Gina Kolata at The New York Times, scientists have encoding a brief movie in the DNA of living cells using the CRISPR–Cas gene editing technique—a move that could lead to cellular recording of health data. They published their results this week in the journal Nature.
The concept behind DNA data storage is relatively simple. While digital files are essentially stored by recording a series of the numbers 0 and 1, DNA can store the same data by encoding the information into its four nucleobases, A, G, C and T.
As Robert Service at Science reports, scientists have been doing just that since 2012, when geneticists first encoded a 52,000-word book in DNA. Though initially inefficient, over time the technology has improved. In March, a team of researchers reported they had encoded six files, including a computer operating system and a film into synthetic snippets of DNA.
For this latest study, the researchers chose a film of a galloping horse recorded by British photographer Eadweard Muybridge in 1878, one of the first motion pictures ever recorded, captured in an attempt to figure out if running horses ever had all four feet off of the ground.
Researchers used the CRISPR-Cas system to transfer the DNA to the bacteria. This system harnesses the power of the bacterial immune defenses to alter the bacteria's DNA, explains Ian Sample for The Guardian. When viruses invade, bacteria sends out enzymes to cut apart the virus' genetic code. And it incorporates fragments of the virus DNA into its own structure to remember the invader in case of future attacks. Scientists can manipulate this system, controlling which bits of DNA hitch a ride into the bacterial genome.
The researchers created a synthetic strand of DNA containing a five-frame block of this video as well as an image of a hand—the letters of the nucelobases representing the shade and position of each images' pixels. "The scientists then fed the strands of DNA to E. coli bacterium" writes Sample. "The bugs treated the strips of DNA like invading viruses and dutifully added them to their own genomes."
“We delivered the material that encoded the horse images one frame at a time,” Harvard neuroscientist Seth Shipman, first author of the study tells Sample. “Then, when we sequenced the bacteria, we looked at where the frames were in the genome. That told us the order in which the frames should then appear.”
As Sample reports, researchers allowed the bacteria to multiply for a week, passing the DNA down through many generations. When they sequenced the genome of the bacteria they were able to reconstruct the encoded images with 90 percent accuracy.
While it would be cool to have The Lord of the Rings trilogy encoded in your DNA one day, Shipman tells Kolata that’s not really the point of this particular research. Instead, he hopes that the technique could lead to molecular recorders that could collect data from cells over time.
“We want to turn cells into historians,” Shipman says in a press release. “We envision a biological memory system that’s much smaller and more versatile than today’s technologies, which will track many events non-intrusively over time.”
Ultimately, Shipman hopes to use the technique to study the development of the brain. Instead of trying to observe brain cells through imaging techniques or via surgery, these molecular recorders would collect data over time from every cell in the brain, which could then be decoded by researchers.
But that day is still a ways off and the current research is just a proof of concept. “What this shows us is that we can get the information in, we can get the information out, and we can understand how the timing works too,” Shipman tells Sample.
While Shipman is focused on health, the tech world is also taking notice of these DNA studies. Antonio Regalado at MIT Technology Review reports that in May, Microsoft announced that it is developing a DNA storage device and hopes to have some version of it operational by the end of the decade. The advantages of DNA storage are pretty obvious, Regalado reports. Not only does DNA last a thousand times longer than a silicon device, it can hold a quintillion bytes of data in one cubic millimeter. Every movie ever made could be stored in a device smaller than a sugarcube. The move could eventually end the days of massive, energy sucking data centers that are required to keep track of everything from great literature to vacation photos.