DNA strand with code

I remember the days when computers had a storage capacity of 40 MB.A few years after it is incresed and become 1 GB hard drive, and today,1 TB is quite the standard and we can see the growth by a factor of about 250.000. However, data storage capacity has slowed down its tumultous develpoment in the last couple of years, but researchers are still working and they are trying to find the next big thing,as a matter of fact, the next big thing could actually be biological ie. our DNA, to be more precise.Researchers have shown that a single cup of DNA can store 100 million hours of HD video and this is just the first results.

As we know that the cost of storage is rising but our budgets are not, as Dr. Nick Goldman of the European Bioinformatics Institute at Hinxton, UK told The Economist (in its January 26, 2013 issue). Goldman (together with 4 colleagues at Hinxton and 2 from Agilent Technologies, California, U.S.) decided to use DNA (yes, the molecule which stores the code to make life possible) as the information storage device, rather than electronics. Their paper titled “Towards practical, high-capacity, low maintenance information storage in synthesized DNA” has just been published in the journal Nature two weeks ago (doi:10.1038/nature 11875).
Why they choose DNA?

I think the question should be Why not DNA.

It is a long chain that consists of 4 alphabets chemical units called bases and referred to as A, G, C and T and that are put together in a string of sequence — similar to what the English language does with its 26 alphabets and punctuation marks, or digital computers with the combination of zeros and ones in chosen sequences.

DNA has been used since life was born over 2 billion years ago to store and transfer information right through evolution. It is small in size — the entire information content of a human is stored in a 3 billion long sequence of A, G, C and T, and packed into the nucleus of a cell smaller than a micron (thousandth of a millimetre). It is stable and has an admirable shelf life. People have isolated DNA from the bones of dinosaurs dead about 65 millions ago, read the sequence of bases in it and understood much information about the animal. The animal (shall we say the ‘host’ of the DNA) is long since dead but the information lives on.

We already know that DNA is a robust way to store information because we can extract it from wooly mammoth bones, which date back tens of thousands of years, and make sense of it. It is also incredibly small, dense and does not need any power for storage, so shipping and keeping it is easy said by Goldman in a statement.
The method is complex, and to accomplish their goals, they emplyed the help of bio-analytics instrument maker Agilent Technologies, a former lab of Hewlett-Packard, to help synthesize DNA from encoded digital information—in this case, an MP3 of Martin Luther King’s I Have a Dream speech – quite a suitable tune.
“We knew we needed to make a code using only short strings of DNA, and to do it in such a way that creating a run of the same letter would be impossible,” Goldman explained. “So we figured, let’s break up the code into lots of overlapping fragments going in both directions, with indexing information showing where each fragment belongs in the overall code, and make a coding scheme that doesn’t allow repeats. That way, you would have to have the same error on four different fragments for it to fail—and that would be very rare.”