DNA as an information storage device

Scientists have been able to store 2.2 petabytes in one gram of DNA

Since time immemorial, mankind has wanted to share and use information for later use. First, it was through the caveman paintings and symbols. Then we invented the alphabets, ideograms, numbers and other symbols. Using these, books were written and stored for future generations, in palm leaves, papyrus sheets or paper. The invention of printing brought the Gutenberg revolution, making multiple copies easily and spreading education to millions of people.

Printed books occupy space. Libraries and archives are bursting at the seams. Enter the computer age and digitization using the binary code of combining zeros and ones (0,1) for alphabets and other such symbols, and reading them using the on-off electrical signals, which has made electronic storage possible, cutting down the size and space for ‘hard copies’. Integrated circuits, processors and related electronic wizardry have shrunk the size of computers and storage devices from room-size to finger nail size.

But even so, the amount of information storable in a given ‘hard drive’ is growing exponentially. “That means 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 he together with 4 colleagues at Hinxton and 2 from Agilent Technologies, California, U.S decided to use DNA  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 .

Why DNA? Indeed the question should be ‘why not DNA”. It is a long chain, consisting of 4 alphabets (chemical units called bases and referred to as A, G, C and T) 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.

DNA is thus a long-lived, stable and easily synthesized storage hard drive. While the current electronic storage devices require active and continued maintenance and regular transferring between storage media (punched cards to magnetic tapes to floppy disks to CD...), DNA based storage needs no active maintenance. Just store in a cool, dark and dry place!

In the Hinxton method , they moved away from the conventional binary (0 and 1) code and used a ternary code system (three numerals 0, 1 and 2 using combinations of the bases A, G, C and T) and encode the information into DNA. This novelty avoids any reading errors, particularly when encountering repetitive base sequences. Also, rather than synthesize one long string of DNA to code for an entire item of information, they broke the file down to smaller chunks, so that no errors occur during synthesis or read-out. These chunks are then read in an appropriate manner or protocol, providing for 100 per cent accuracy.

How much information can be stored in DNA?

Goldman and co have been able to store 2.2 petabytes (a peta is a million billion or 10 raised to power 15) in one gram of DNA.

What about the speed? And how does one read the files?

Today, the speed is slow and the reading using DNA sequencers is expensive, but in time both the speed will improve and the cost come down considerably.

What did Goldman and group store in DNA?

For starters, they stored all 154 sonnets of Shakespeare (in ASCII text), the 1953 Watson-Crick paper on the DNA double helix (in PDF format), a colour photograph of Hinxton (in JPEG) and a clip from the “I have a Dream” speech of Martin Luther King (in MP3 format).

Natural selection and evolution have used DNA to store and read out to make our bodies. And we are now using DNA to store and archive the products of our brains. What a twist!

Posted By

Linda.R

HOS-LP2

BIS 

[Source: The Hindu News Paper]

ICT in Students Life

Information and communication technology have recently gained groundswell of interest. Its nature has changed the face of education over the last few decades.

For many counties the use of ICT in education and training has become a priority during the last decade. However very few have achieved progress. Indeed a small percentage of schools in some countries achieved high level of effective use of ICT to support and change the teaching and learning process in many subjects’ areas. Schools with higher level of e- maturity shows a rapid increase in performances in scores compared to those with lower level. To achieve better results in the performances of learners, the teachers should be more convinced in the good use of ICT in classrooms.

Many pupils consider ICT tools very helpful in that it helps them to do assignments and other works. ICT enables the students to meet their special needs or difficulties. It also helps to reduce the social disparities between pupils, since they work in teams in order to achieve given task.

Students also assume responsibilities when they use ICT to organize their work through digital portfolios or projects. In addition it shows that ICT has significant impact on teachers and teaching processors.

ICT help the teachers to plan their lessons more efficiently and to work in teams and share ideas related to schools curriculum.

There is also evidence that broadband and interactive whiteboards play a central role in fostering teachers communication and increasing collaboration between educators. ICT can improve teaching by enhancing and already practiced knowledge and introducing new ways of teaching and learning.

By providing a good fit with exiting practices such as interactive whiteboards and other  tools like  video conference ,digital videos and virtual stimulating the class rooms will be better and effective than  a traditional classroom environment  

Fathima.P

Librarian

BIS