In a recent study published in the journal Nature titled "A time-resolved, multi-symbol molecular recorder via sequential genome editing," a group of researchers from the University of Washington describe their recent experiments with recording information directly onto living cells with a "DNA Typewriter." From the abstract:
DNA is naturally well suited to serve as a digital medium for in vivo molecular recording. However, contemporary DNA-based memory devices are constrained in terms of the number of distinct 'symbols' that can be concurrently recorded and/or by a failure to capture the order in which events occur1. Here we describe DNA Typewriter, a general system for in vivo molecular recording that overcomes these and other limitations.
With the itself DNA functioning as the "tape" or blank recording medium, the researchers used CRISPR-Cas9 to insert the information into a specific segment of the DNA. Or, as phys.org explained it:
The idea to use DNA to encode information piggybacks on the molecule's natural function. Just as computer software is written in 1s and 0s, the DNA molecule uses a four-letter code for the instructions for living things.
The DNA typewriter isn't the first of its kind, however, it has a combination of attributes that make it particularly promising for illuminating the biology of cells. Namely, it can capture a large number of events while documenting them in chronological order.
Put another way, it's like Morse code — but instead of dots and dashes, you insert combinations of Cs, Gs, Ts, and As into the DNA strand.
To demonstrate their proof of concept, the researchers thought long and hard about exactly what information to encode into the model DNA strand. What should be the first thing that other people see when they read the information on this historic strip of DNA? A Biblical reference? A tip of the hat to Alexander Graham Bell's first telephone call? Nah — they decided to pay homage to lead author Junhong Choi's Korean heritage by referencing a lyric from K-pop sensations BTS: "Bound forever, DNA."
A time-resolved, multi-symbol molecular recorder via sequential genome editing [Junhong Choi, Wei Chen, Anna Minkina, Florence M. Chardon, Chase C. Suiter, Samuel G. Regalado, Silvia Domcke, Nobuhiko Hamazaki, Choli Lee, Beth Martin, Riza M. Daza & Jay Shendure / Nature]
DNA typewriter taps out messages inside cells [Howard Hughes Medical Institute / Phys.org]