Genomic DNA contains four fashioned nucleotides, every with a particular nucleobase: adenine (A), thymine (T), cytosine (C), and guanine (G). These nucleobases create the genetic alphabet, ATCG, which is conserved all over all domains of life. Alternatively, in 1977, the DNA virus cyanophage S-2L became came all over with all cases of A substituted with 2-aminoadenine (Z) for the length of its genome (1, 2), forming the genetic alphabet ZTCG. Reports printed attention-grabbing properties of Z-substituted DNA (dZ-DNA) (3–6), but minute of Z synthesis became understood. On pages 516 and 512 of this articulate, Sleiman et al. (7) and Zhou et al. (8), respectively, signify viral Z biosynthesis. On page 520, Pezo et al. (9) name a Z-explicit DNA polymerase that is to blame for assembling dZ-DNA from nucleotides. All three experiences name extra “Z-genomes” in diverse bacteriophages (viruses that infect bacteria), which would possibly perchance perchance also fair hang offered evolutionary advantages alongside fashioned ATCG DNA since life began.