Using the T-REX method, DNA embedded in a polymer can be used for long-term storage of genomes or digital data such as photos and music.

A new polymer developed by MIT researchers offers a major advance in DNA storage, making it possible to preserve it at room temperature without the energy costs associated with traditional freezing methods. This technology not only stores large volumes of data efficiently, but also provides easy access and intact DNA, making it a promising solution for both genetic and digital archives.

Advances in DNA preservation technology

In the movie Jurassic Park, scientists extracted DNA that had been preserved in amber for millions of years and used it to create a population of extinct dinosaurs. Inspired in part by that movie, MIT researchers have developed a glassy, ​​amber-like polymer that could be used for long-term storage of DNA, whether it’s entire human genomes or digital files like photographs.

Most current DNA storage methods require low temperatures, so they are energy intensive and not feasible in many parts of the world. In contrast, the new amber polymer can store DNA at room temperature, protecting the molecules from damage caused by heat or water.

Researchers showed that they could use this polymer to store DNA sequences that code for the Jurassic Park soundtrack and the entire human genome. They also showed that DNA could be easily removed without damaging the polymer.

Improving DNA preservation methods

“Freezing DNA is the number one way to preserve it, but it is very expensive and not scalable,” says James Banal, a former MIT postdoctoral researcher. “I think our new preservation method will be a technology that could facilitate the future of storing digital information in DNA.”

MIT Chemistry Professor A. Thomas Guertin Banal and Jeremiah Johnson are senior authors of the study, published June 12 in the journal. American Chemical Society. Former MIT postdoctoral researcher Elizabeth Prince and MIT postdoctoral researcher Ho Fung Chen are the lead authors of the paper.

Examination of new DNA coding methods

DNA is a very stable molecule, which makes it well-suited to storing very large amounts of information, including digital data. Digital storage systems encode text, photographs, and other information as a series of 0s and 1s. The same information can be encoded in DNA using the four nucleotides that make up the genetic code: A, T, G, and C. For example, G and C can be used to represent 0, while A and T can represent 1.

DNA offers a way to store this digital information at very high density: In theory, a cup of coffee filled with DNA could store all the data in the world. DNA is also very stable and relatively easy to synthesize and sequence.

In 2021, Banal and postdoctoral fellow Mark Bath, a professor of biological engineering at MIT, developed a way to store DNA in silica particles that could be tagged with labels that reveal the contents of the particles. This work led to a development called Cache DNA. One of the disadvantages of this storage system is that it takes several days for the DNA to be embedded in the silica particles. Additionally, extracting DNA from particles requires hydrofluoric acid, which can be hazardous to workers handling DNA.

Innovative polymer design for DNA storage

Banal began collaborating with Johnson and members of his laboratory to create alternative storage materials. Their idea was to use a type of polymer known as thermosettable, which consists of polymers that form solids when heated. The material also contains fissile links that can be broken easily, allowing controlled degradation of the polymer.

“Depending on what breakable bonds we put into these thermosets, we can choose how we want to degrade them,” Johnson says.

For this project, the researchers decided to make thermosetting polymers from styrene and a crosslinking agent; together these formed a reactive, amber-like material called cross-linked polystyrene. This thermosetting material is also highly hydrophobic, so it can prevent moisture from entering and damaging DNA. To degrade the thermosetting material, styrene monomers and cross-linkers are copolymerized with monomers called thionolactone. These bonds can be broken by treatment with a molecule called cysteamine.