If you don't substitute two amino acids, if you don't say ATXY, if you say ATCG + XY, then you go from 20 building blocks to 172, and all of a sudden you've got 172 building blocks of amino acids to build life-forms in very different shapes.
Si no substituïm dos amino àcids, si no diem ATXY, si diem ATCG + XY, aleshores passem de 20 blocs de construcció a 172, i de sobte tenim 172 blocs d'amino àcids per construir formes de vida d'aspectes molt diferents.