Researchers look to DNA for data storage
In what can be termed as a breakthrough in the field of data storage, scientists in Britain have now come with forward with a revolutionary technique to turn DNA into a new form of data storage. According to them, a speck of man-made DNA can hold mountains of data that can be freeze-dried, shipped and stored, potentially for thousands of years.
The information is “read” by sequencing the DNA –similar to how it’s done in genetic fingerprinting and so on – and then reversing it back into computer code.
“We already know that DNA is a robust way to store information because we can extract it from bones of woolly mammoths, which date back tens of thousands of years, and make sense of it,” said Nick Goldman of the European Bioinformatics Institute (EBI) in Cambridge.
“It’s also incredibly small, dense and does not need any power for storage, so shipping and keeping it is easy.”
DNA, short for Deoxyribonucleic acid, is a double helix structured molecule — a long, coiled molecular “ladder” comprising four chemical rungs: adenine (A), cytosine (C), guanine (G) and thymine (T). These rungs always team up in pairs, C teams up with G, and T teams up with A.
The way these letters are sequenced in the DNA comprises the genome, or the chemical blueprint for making and sustaining life. Human DNA consists of more than three billion letters, coiled into pairs of 24 chromosomes.
The project entails taking data in the form of 0s and 1s in binary code, and transcribing it into “Base-3″ code, which uses zeros, 1s and 2s. The data is then transcribed for a second time into DNA code, which is based on the A, C, G and T. A block of five letters is used for a single binary digit and the letters are then turned into molecules, using lab-dish chemicals.
No living DNA is used and nor does the project seek to create any artificial life form. In fact the man-made code would be quite meaningless in the biological world.
“We have absolutely no intention of messing with life,” said Goldman.
As only short strings of DNA can be made, the data has to be divided into small sections of 117 letters, each attached to a tiny address tag which can be reassembled later.
The team has already encoded various files using this technique such as an MP3 recording of Martin Luther King’s “I Have A Dream” speech; a digital photo of their lab; a PDF of the landmark study in 1953 that described the structure of DNA; a file of all of Shakespeare’s sonnets; and a document that describes the data storage technique.
The team used standard sequencing machines to unravel the code and they were able to recover and read the files with 100-percent accuracy. The new method eliminates the risk of error when the DNA is read, say the researchers, whose work appears in the journal Nature.
With data storage expanding massively around the world, storing it is becoming a major challenge. Magnetic and optical discs take up a lot of space and need to be kept in cool, dry conditions. And moreover they have very short life expectancies, a disadvantage for extremely important backups.
“The only limit (for DNA storage) is the cost,” said Birney.
Sequencing and reading the DNA takes a couple of weeks with present technology, so it is not suitable for jobs needing instant data retrieval. But it would be suitable for data that would be stored for between 500 and 5,000 years, such as an encyclopedia encompassing all of human knowledge and culture.
With progressing technology, the sequencing costs could fall by a factor of 20 within a decade and perhaps the reading time would improve too, making DNA storage economically feasible for time frames of less than 50 years.
Salman Ravoof is a freelance writer, a mechanical engineer and an avid science and technology enthusiast. He likes creativity and is a great fan of fantasy and sci-fi genre. When not busy, he revels in experimenting and spends most of his time pondering about the existence of reality.
29 January, 2013