Carl Zimmer in his excellent blog, The Loom:
This old English major’s heart is warmed by the news that the new synthetic cell carries a line from James Joyce, inscribed in its DNA: “To live, to err, to fall, to triumph, to recreate life out of life.”
What would Joyce have thought if someone had told him that one day the synthesized genome of a goat pathogen would carry his words? I would hope that whoever told him would make sure that he did not think this moment marked his literary immortality. In fact, his deathless prose is probably being desecrated by the relentless erosion of evolution right now.
The scientists who produced the new synthetic cell copied the genome of a microbe, letter for letter, and then inserted the synthetic version into a host cell. To determine that their experiment worked, they needed a way to tell the genomes of their synthetic cells from the natural genomes that were their model. So they inserted “watermarks” into the artificial genome. These sequences of DNA (which spelled out the work of Joyce and others through the genetic code) sit in non-coding regions of the microbe’s DNA. As a result, these watermarks cannot disrupt any essential protein-coding genes or stretches of DNA that are vital for switching genes on and off.