The work, carried out by George Church and Sri Kosuri, basically treats DNA as just another digital storage device. Instead of binary data being encoded as magnetic regions on a hard drive platter, strands of DNA that store 96 bits are synthesized, with each of the bases (TGAC) representing a binary value (T and G = 1, A and C = 0).
To read the data stored in DNA, you simply sequence it — just as if you were sequencing the human genome — and convert each of the TGAC bases back into binary. To aid with sequencing, each strand of DNA has a 19-bit address block at the start (the red bits in the image below) — so a whole vat of DNA can be sequenced out of order, and then sorted into usable data using the addresses.
Scientists have been eyeing up DNA as a potential storage medium for a long time, for three very good reasons: It’s incredibly dense (you can store one bit per base, and a base is only a few atoms large); it’s volumetric (beaker) rather than planar (hard disk); and it’s incredibly stable — where other bleeding-edge storage mediums need to be kept in sub-zero vacuums, DNA can survive for hundreds of thousands of years in a box in your garage.
It is only with recent advances in microfluidics and labs-on-a-chip that synthesizing and sequencing DNA has become an everyday task, though. While it took years for the original Human Genome Project to analyze a single human genome (some 3 billion DNA base pairs), modern lab equipment with microfluidic chips can do it in hours. Now this isn’t to say that Church and Kosuri’s DNA storage is fast — but it’s fast enough for very-long-term archival