Every single day, we generate information. We look up things on Google, spend time posting on social media, or watch videos on YouTube, to name a few examples. In 2020, it was estimated that about 418 zettabytes of information were created by the whole of the Earth’s population – that is 418 with 21 zeroes after it, or to put it in context, possibly much more than the capacity of 500 billion computers. The amount of information only increases more and more with each year that passes.
In the near future, we will reach a point when our current data-storage systems will not be able to keep up with the exponential increase in information. Data centres require huge amounts of energy, and are not cheap. Plus, they will eventually take up a lot of space. Building more centres like these and maintaining them in the appropriate conditions will become very expensive over time.
An alternative that is now being explored is the use of DNA as new hard drives. Living organisms are more like computers than we think. Our genetic information – basically, all that we are – is coded in the cells of our body in what we call nucleotides: A (adenine), C (cytosine), T (thymine) and G (guanine). You can compare these to the ones and zeroes in binary that computers use. These letters make up our genetic material, and combine in different ways to give each individual certain characteristics that makes them unique and different from the rest.
Why use DNA? Well, DNA can pack very tightly: a single cell in our body contains about 2 metres of extended DNA, and it can all fit in a cell with a radius of 0.1 mm in diameter. Plus, in the right conditions, DNA molecules can be maintained for hundreds of years before they begin to degrade.
So, if our DNA can store all of the information needed to create a living creature and make it work properly, why not use it to store other information? In fact, several companies, including Microsoft, are working towards making this a reality. You can think of the four letters (A,C,G,T) as combinations of two digits: 11, 01, 10, 00. The digital data that is encoded in binary is broken down into pairs of numbers, and a letter (nucleotide) is assigned to each pair. These nucleotides are then placed in order to make long DNA chains, which can then be folded over and over until they fit inside cells. Then the process can be reversed to decode the information.
However, there is still a lot to improve. As DNA is so tightly packed, it has to be previously unpacked so that the information can be handled, which is quite a slow process. Also, the reading of the DNA is an expensive process, as it has not been completely refined yet.
One thing is for sure: there will be a day where all of the information we look up will be stored in DNA!