Identifies the rules for the "kill code“ and the basis of NUAgo’s Class-1 technology through a screen of all possible combinations of 6mer seeds sequences (4096 sRNAs) with G-rich seeds targeting C-rich seed matches in the 3' UTR of a set of survival genes. These survival genes contain C-rich sequences near the beginning of their 3' UTR. miR-34-5p family of miRNAs effect is through this mechanism. Additionally, the Peter Lab describes that the kill code is evolutionally conserved and at least 800-million-year-old. Finally, this paper describes first evidence that chemotherapeutic drugs engage the 6mer seed toxicity mechanism and that cells devoid of most miRNAs (e.g., Drosha or Dicer ko cells) are hypersensitive to anything that acts through this kill mechanism.