Schultz's work (as I've understood) modified tRNA to alter the genetic code[0] which converts nucleobases into amino acids. This allows for a different code com

Schultz's work (as I've understood) modified tRNA to alter the genetic code[0] which converts nucleobases into amino acids. This allows for a different code compared to the one found in nature. This work, on the other hand, adds 2 new nucleobases to the existing 4 bases. That's not the same. IMHO it's a very different and novel work: in principle the genetic code can now accept an alphabet of up to 216 amino acids, compared to 64 previously (with nature essentially using 20 of those; this assumes three-nucleotide codons). It's true that Schultz's work, at a higher level, is necessary for this to be of any practical use. But this work has significant additional benefit on its own: for example, I believe you could immediately construct a genetic code that used the additional redundancy to be far more stable against mutation. [0]https://en.wikipedia.org/wiki/Genetic_code https://en.wikipedia.org/wiki/Genetic_code