A great deal of information about a person is stored within their DNA. For example, their height, blood type, and particulars of their metabolism and immune system are all in that double helix. While all of this information is important for life, it is not so important for computation. Researchers at the Stanford University Medical Center have spent the past three years to develop a mechanism to make DNA a viable means of binary data storage. It took 750 attempts, but the researchers finally have their rewriteable bit.
For some time researchers have been able to use specific enzymes to flip sections of DNA from one direction to another. What has required all of this work was finding the balance between two of them, so the DNA section can be flipped back and forth when desired. Computer-literate people will call this nonvolatile memory, as the bits do not require energy to be stored as they are. Biotechnologists however will call it recombinase-mediated DNA inversion, but the name of the device is a blending of the two fields; recombinase addressable data (RAD) module.
This is definitely an important step towards the development of computers built into biological systems, but there is more work to do. This is just a bit of data after all, and the researchers believe it will take about a decade before we see a full byte encoded into DNA. While that may seem like a very long time, the researchers do believe the work will accelerate as they get to it, with each additional bit being easier to make than the previous.