Reportedly, scientists at the Harvard Medical School in Boston were able to devise a system permitting them to store "an entire genetics textbook in less than a picogram of DNA -- one trillionth of a gram -- an advance that could revolutionize our ability to save data."
A few teams have tried to write data into the genomes of living cells. But the approach has a couple of disadvantages. First, cells die -- not a good way to lose your term paper. They also replicate, introducing new mutations over time that can change the data.
To get around these problems, a team led by George Church, a synthetic biologist at Harvard Medical School in Boston, created a DNA information-archiving system that uses no cells at all. Instead, an inkjet printer embeds short fragments of chemically synthesized DNA onto the surface of a tiny glass chip. To encode a digital file, researchers divide it into tiny blocks of data and convert these data not into the 1s and 0s of typical digital storage media, but rather into DNA's four-letter alphabet of As, Cs, Gs, and Ts. Each DNA fragment also contains a digital "barcode" that records its location in the original file. Reading the data requires a DNA sequencer and a computer to reassemble all of the fragments in order and convert them back into digital format. The computer also corrects for errors; each block of data is replicated thousands of times so that any chance glitch can be identified and fixed by comparing it to the other copies.