Enzymatic synthesis and nanopore sequencing of 12-letter supernumerary DNA

Using the canonical rules of DNA base-pairing (size and shape complementarity), it is possible to construct 6 orthogonal base pairs consisting of 12 bases (the natural bases A, T, C, and G, and xenonucleotides P, Z, S, B, X, K, J, and V). The Marchand group devised a method for enzymatically writing any of these bases into a DNA strand.  Once written, they wanted to "read" these bases off using nanopore DNA sequencing. Our group helped with design and analysis of the nanopore sequencing experiments. The result is the first synthesis and first sequencing of a DNA strand which includes all 12 possible hydrogen-bonding base pairs.