The Data-Storage Challenge

The amount of digital information being created today is growing at a dizzying pace. According to some estimates, by 2025, there will be five times more digital data than there was in 2018 (Figure 1), and it all needs to be stored somewhere. This huge rise in data is driven by several things, including the use of smartphones, social media, and new technologies like artificial intelligence (AI). These technologies create various types of data, such as personal information, social media posts, business records, medical statistics, sensor data, and other types of digital information stored on computers.

As technology becomes more advanced, we create more and more information that needs to be stored and accessed easily. It might seem like having more information is a good thing, but there is a problem. The challenge is figuring out how to store this growing stockpile of information. Specifically, we are approaching a point where our current storage technologies cannot keep up with the amount of data that is being created. This has far-reaching implications because our technological world depends on the ability to store digital information effectively.

You might have heard people say that saving files on the cloud gives you endless storage, as if the cloud were an infinite, invisible space. But this is not true. In reality, the cloud is not invisible; it is made up of huge storage centers, sometimes as big as several football fields. These centers hold thousands, or even millions, of computers that store and manage enormous amounts of digital information. Not only do they take up a lot of space, but they also use as much electricity as a midsized city. This means that storing information this way is not sustainable, so we must find better ways to store data (Figure 2).

DNA-Based Data Storage

When we talk about storing information, there are a few important things to think about. First, the storage solution should be able to hold a lot of information. Second, it should be good for the environment. And third, it should last a long time. One exciting idea that can do all of these is using synthetic DNA molecules to store digital information. But how does this work? And what makes DNA a good choice for storage?

DNA is a special molecule found in the cells of every living thing, from tiny bacteria to humans. DNA holds all the genetic information needed to create life. You can think of a DNA molecule as a long chain made up of four “building blocks”: adenine (A), guanine (G), thymine (T), and cytosine (C). The order in which these four building blocks are arranged in a chain is unique to each living organism. For a long time, scientists have known how to “read” the exact order of the four building blocks in a DNA molecule, using a process called DNA sequencing [1]. More recently, scientists have learned how to design and create synthetic DNA in the lab by putting the building blocks together in almost any order they like.

Why DNA?

Compared to other ways we store digital information today, DNA molecules have some important advantages. First, although DNA molecules are tiny, they can hold an enormous amount of information. Using DNA for information storage would mean we would not need the huge storage centers used today, which take up a lot of space and energy. For example, if we store many DNA molecules containing digital data in a storage container the size of an average person, this container could hold 150 billion terabytes of data! That is an incredible amount of storage, equivalent to about 150,000 storage centers.

The second advantage is that DNA has a stable structure that can last a very long time. In fact, scientists can even sequence DNA from fossils of creatures that roamed the Earth hundreds of thousands of years ago. For this reason, digital information could be stored and preserved in DNA for a very long time, unlike our current storage technologies, which usually last only 3–30 years. Finally, DNA does not need a constant source of electricity to keep the data stored. This could save a lot of energy, making DNA-based data storage an environmentally friendly solution.

Translating Digital Information Into DNA Language

How do we take digital information, like a music file, video, or image, and put it on a tiny DNA molecule? The secret lies in the language! Digital information is stored on computers using the binary language, which consists of only two digits: 0 and 1. On the other hand, DNA’s genetic code uses a language made up of four letters: A, C, G, and T. If we can translate between these two languages, we could store a lot of digital information in tiny DNA molecules. Essentially, we translate information currently in binary language into DNA language and then create the matching synthetic DNA molecules and store them.

To translate one language into another, we need common ground to connect them. If we look at the binary language, we can take the numbers 0 and 1 and pair them together into four combinations:

00

01

10

11

These four combinations work perfectly because they can match the four letters in the DNA language. So, we can replace each binary pair with a DNA letter:

00 becomes A.

01 becomes C.

10 becomes G.

11 becomes T.

For example, let us take the binary sequence 00010011111001001. We can split it into pairs and mark each pair with a color like this:

00 01 00 11 11 10 01 00 11

Now, we translate each binary pair into a DNA letter:

A C A T T G C A T.

Remember, this is just a simple example. In real life, scientists use more advanced methods to ensure that the information stays safe and accurate, even if there is a mistake in the system [2].

Storing Digital Information in DNA

After the binary code is translated into DNA language, there are several more steps in the data-storing process [3], which are summarized in Figure 3.

First, due to technology limitations, the DNA molecules we can make in the lab are short, which is a problem, because our files can be much larger then what can be stored in a single molecule. Therefore, we must cut our digital files into smaller sections before each piece is written in binary language. The binary information is then translated into DNA language as we just explained, with the help of a computer program. Finally, in the lab, we create the desired DNA molecules using advanced equipment. Interestingly, when we make one molecule, a lot of nearly identical copies are produced at the same time. All of these molecules are stored together in storage containers without any specific order. That is, DNA molecules are stored in a pool in a way that is similar to shredding multiple copies of the same book into a million fragments and mixing all the book fragments in a box. Sometimes, errors can happen during this process, which can affect some of the molecules. This can be thought of as losing some of the book fragments, and having typos in some of the remaining fragments (e.g., “Cat” becomes “Cut”).

Retrieving Data From DNA Storage

At this point, the digital information has been successfully transferred into synthetic DNA molecules, which can be stored for a very long time. At any time in the future, we can retrieve the data from these molecules and transform it back into the original digital files. The first step in this process is to read the stored DNA molecules using DNA sequencing. This process gives us a collection of words in the DNA language created by DNA’s four building blocks. Then, we translate the DNA words back into binary language, which recreates the original digital file. A computer program helps with this step, too.

Summary and Main Points to Remember

In this article, we explored the challenges of storing digital information and introduced an exciting new solution: synthetic DNA molecules. While we still have a long way to go before we can upload information into a DNA-based cloud, there are ongoing efforts to reduce costs and improve the technology. The next time you take a picture or watch a video, consider where that information is stored. Soon, you might be able to save your own digital data on a synthetic DNA molecule, which can hold a huge amount of information for a very long time while also being environmentally friendly. This incredible achievement might be made possible by bridging the worlds of biology and computer science.

Glossary

Artificial Intelligence (AI): ↑ Computer systems or machines that mimic human intelligence to perform tasks.

Sustainable: ↑ A way of using resources without damaging the environment or using up resources needed by future generations. Sustainable solutions are important for protecting our planet over time.

Synthetic DNA: ↑ DNA molecules created in the lab, which are not derived from natural sources.

DNA Sequencing: ↑ A laboratory technique used to determine the exact order of the four letters that make up a DNA molecule. DNA sequencing allows scientists to “read” the information stored in DNA.

Binary Language: ↑ The language used for computers, in which information is represented by combinations of only two numbers, 0 and 1.

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments

This work was supported by the European Union (DiDAX) under Grant 101115134.

Author Disclaimer

Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them.