A 1977 scientist found the S-2L virus which infects cyanobacteria, This virus does not encode adenine, This instead codes for diaminopurine, shortened to Z. This derivative will make 3 hydrogen bonds instead of adenine's 2. This is incredibly interesting as we can see the genetic mutations occurring in this virus that allows it to use a whole entire new coding language. perhaps eventually even humans will use this coding language as well!!