The researchers of the North Carolina State University have turned a long-standing DNA data storage challenge into a tool to use it to offer the previews of stored data files, for instance, the thumbnails of image files, that have the capacity to retain a large amount of data in a small package, and can save this data for a long duration in an energy-efficient way. Till now, it was not possible to preview the data of a saved file stored as DNA, and anyone who wishes to know what is inside the file has to open the entire file. “The advantage of this technology is that it is comparatively more time and cost effective technique,” says Kyle Tomek, lead author on thesis and PhD student at NC State. If you're not sure of the file which contains the data that you need, then, you need not to sequence the entire DNA in all the potential files, rather you can sequence the smaller pieces of the DNA files which will serve as a preview.
Users name their data files by appending DNA sequences called primer binding sequences to the ends of strands of DNA that store information. To identify and extract a specific file, most systems use the polymerase chain reaction (PCR). Specifically, they use a small DNA primer that corresponds to the binding sequence of the appropriate primer to identify the DNA strands that contain the desired file. The system then uses PCR to make many copies of the relevant strands of DNA and then sequence the entire sample. Copies of the target DNA strands, and the signal from the target strands is stronger than the rest of the sample, making it possible to identify the target DNA sequence and read the file. However, one challenge faced by DNA data storage researchers is PCR accidentally copies portions of multiple data files when two or more files have similar file names. Therefore, users have to name files very differently to avoid data confusion.
“At some point it occurred to us that we could use these non-specific interactions as a tool rather than viewing them as a problem,” says Albert Keung, correspondent co-author of a paper on the work and assistant professor of chemistry and biomolecular engineering at the NC state The researchers developed a technique that uses similar file names to open an entire file or a specific subset of that file. This works by using a specific naming convention when naming a file. They can opt whether to open the entire file or just the “preview” version by manipulating various parameters of the PCR process such as temperature, DNA concentration in the sample, the reagent types and concentrations in the sample.