By Jenny Tang
DNA Hard drives (DNA-HD) are based off DNA nanotechnology and nano pores which are achieved by reading molecules, one by one per millisecond using nanopores. This is done by annealing 7228 nucleotides stranded DNA, creating a scaffold. Taking advantage of the negative charge of DNA, it can be read by nanopore sensing which translate into ionic current signals.
DNA-HD would assist in the storage of digital data, as the amount of data has grown exponentially within the past few days and data keeping has become more and more of an issue. DNA-HD are able to compile enormous amounts of data into a compact chip. In comparison to silicon chips that we currently use to compile data, DNA-HD is superior as it is much more resilient and harder to eradicate. In one experiment, two long documents were translated into 83kB to 4991 DNA segments.1 These DNA segments were synthesized on CustomArray, an electrochemical microarray technology, and sequenced through PCR. They were later encapsulated into silica, and stored in a heated environment at roughly 70 °C for a week. Afterwards, the sequences were read through Illumina MiSeq platform, with only around 0.7nt errors per sentence, which is a relatively high accuracy. Information vulnerability is also an issue in modern days’ time, which DNA-HD solves, as it is much more difficult to read, leading to it being a much more secure option.2
DNA is miniscule in size, to the extent that it is invisible to the human eye. The size of DNA, averages around two nanometres in width, meaning that DNA is extremely thin and long.3 The combination of the long DNA strand, and extreme thin nature of DNA, allows it to be compactly stored. This means that DNA-HD can be stored easily, in comparison to a transcript stored on a computer, where there is a limitation to the amount of data that could be stored. In comparison to a hard drive, a DNA-HD is superior in terms of both capacity of data and resilency.
The current disadvantage to DNA-HD is the fact that it is expensive, with it costing around 3500$ per Mb, and around 1000$ to read the DNA. With the high prices, it is still severely limited and impractical to use commercially.4 Another large issue is the processing time to read and write the DNA. Although accurate in reading the molecules, it takes hours at a time.
Another notable issue is correction or changing the transcript when writing the DNA transcript. Giving the analogy of writing an essay, after you write the essay and you want to correct or change some kind of given detail. This is incredibly difficult with a DNA transcript, as you would have to target a small area of the sequence and change it. When inputting any additional information in the sequence, it would furthermore change the translation of the subsequent sequences.
A numerous number of companies are currently trying to develop DNA storage methods, as it solves many issues of the modern world in terms of data storage, mainly storage space, and data security. A company called Catalog that was funded by scientists from MIT have announced on September 30 2021 that they have raised 35m to create the world’s biggest DNA platform for DNA storage.5 In July 2019, they were able to encode the entirety of the English language Wikipedia into DNA. They have set a goal to be able to reach 160 Zettabytes by the start of 2025.
Along with that, Microsoft Research and UW Molecular Informations lab have created a collaboration and have been able to utilise a fully functional DNA data storage system, which can store a gigabyte of DNA. They aim to investigate different DNA systems and to be able to create cost effective methods and to commercialise DNA storage.6
1. Chen, K., Zhu, J., Bošković, F. and Keyser, U.F. (2020). Nanopore-Based DNA Hard Drives for Rewritable and Secure Data Storage. Nano Letters, 20(5), pp.3754–3760.
2. Grass, R.N., Heckel, R., Puddu, M., Paunescu, D. and Stark, W.J. (2015). Robust Chemical Preservation of Digital Information on DNA in Silica with Error-Correcting Codes. Angewandte Chemie International Edition, 54(8), pp.2552–2555.
3. http://www.ancestry.co.uk. (n.d.). DNA Strands | What are DNA Strands? | AncestryDNA® Learning Hub. [online] Available at: https://www.ancestry.co.uk/lp/double-helix/dna-strands [Accessed 26 Oct. 2021].
4. Panda, D., Molla, K.A., Baig, M.J., Swain, A., Behera, D. and Dash, M. (2018). DNA as a digital information storage device: hope or hype? 3 Biotech, [online] 8(5). Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5935598/.
5. CATALOG. (n.d.). CATALOG. [online] Available at: https://www.catalogdna.com [Accessed 26 Oct. 2021].
6. GeekWire. (2020). Microsoft helps found an industry alliance to advance DNA data storage systems. [online] Available at: https://www.geekwire.com/2020/microsoft-joins-new-industry-alliance-aimed-advancing-dna-data-storage-systems/ [Accessed 26 Oct. 2021].
 Robust chemical preservation of digital information on DNA in silica with error-correcting codes.
Grass RN, Heckel R, Puddu M, Paunescu D, Stark WJ
Angew Chem Int Ed Engl. 2015 Feb 16; 54(8):2552-5.