DNA diaries…Zarrar Khuhro
WHERE and what would we be without deoxyribonucleic acid? What would happen to you if, by some dark miracle, all the DNA in your body simply vanished? You wouldnt feel much to start with, apart from losing the 200 or so grams that your DNA weighs. Then things will start to go bad: your cells will stop replicating and start dying off, much like if you were exposed to a high dose of radiation, and youd be dead in extreme pain within days or hours if youre lucky due to massive organ failure.
Thats because DNA contains the entire blueprint for who we are and how our bodies work. Without venturing too deeply into the nature vs nurture debate, DNA is what makes you you. And as such, it contains a staggering amount of data in a very small package. How much data? Consider that a single gram of DNA can store as much as 215 petabytes of data, and that one petabyte contains a little over 1,000 terabytes. This means that a tiny little gram of DNA can safely store up to 215,000 terabytes, or 215 million gigabytes if you prefer. On the other hand, the average weight of a single terabyte hard drive is about 400g.
In even simpler terms: you could theoretically fit all of the worlds data in a single coffee mug filled with DNA.
Currently, most of the worlds data is stored in an incredibly old-school manner in gigantic facilities known as exabyte data centres, and one of the largest of these The Citadel sprawls over 1.3 million square feet (120,774 square metres), which means it can contain 41 cricket stadiums the size of Lords.
Theyre also very expensive, with some costing as much as a billion dollars to build and maintain. Given that the data needs to be stored at a cool temperature much like a conventional cold storage for perishable products the energy costs are immense. Moreover, the data stored tends to degrade over time and needs to be copied onto newer databases, which is a cumbersome and expensive process. And, at the current rate at which we are producing that data, well need many more such costly and energy-sucking centres to store it.
Therere about 10 trillion gigabytes of data floating around the world today and on a daily basis: our photos, Facebook posts, tweets, emails, etc, add another 2.5m gigabytes, which amounts to something like 1.7 megabytes of data being generated per person per second.
DNA data storage, already being worked on by scientists around the world, could solve this issue for all time to come. Not only will such immense centres no longer be needed, the half-life of DNA is 500 years while stored properly and so our data will be secure for far longer without significant degradation. The biggest problem right now is how to find a cost-effective way to synthesise the amount of DNA that will be needed, as right now it would cost $1tr to write one petabyte of data. Of course, given the need and the exponential rate of scientific progress that we are seeing, the day when we can store data on DNA may not be far off.
Theres another debate thats been raging among scientists ever since the discovery of DNA in 1953, and this is whether DNA can conduct electricity and, if so, how effectively? While the debate remained academic for decades, recent research indicates that DNA molecules can also conduct electricity and self-assemble into well-defined shapes, making them potential candidates for building low-cost nanoelectronic devices.
This will be critical going forward, given that the size of circuits and transistors is shrinking rapidly (the smallest transistor is tinier than the HIV virus) and there will come a time when traditional methods for conducting electricity through these nano-circuits will become impossible. If DNA can be used for this purpose, it would mean that the circuits of the future may be the size of a single molecule or atom.
Speaking of electricity, another significant discovery made just last month is that electrical currents can be used to control human genes. Researchers managed to trigger insulin production in human cells by sending currents to targeted genes through what they call an electrogenetic interface, prompting the cells to produce insulin on their own. What does that mean for us? Simply put, it means that in the near future, diabetics could dispense with insulin injections by simple wearing a device, perhaps no larger than a wristwatch, which would not only monitor insulin levels, but prompt the wearers own genes to produce insulin when required.
This is, of course, just the beginning and, if further tests prove fruitful, the technique could be applied to a variety of human medical conditions, leading to what may be one of the greatest medical breakthroughs of history. It is indeed a miracle that the building blocks of the future may well be the same building blocks that make us who we are.
Courtesy Dawn