History The CRISPR/Cas system evolved in nature as a means for bacteria to protect themselves from invading viruses and bacteriophages by inserting pieces of their DNA into the host genome. This allowed the adaptive immune system to respond accordingly on a subsequent infection.
CRISPR, short palindromic repeating sequences of DNA, found in most bacterial genomes, that are interrupted by so-called spacer elements, or spacers—sequences of genetic code derived from the genomes of previously encountered bacterial pathogens.
What is CRISPR? CRISPR genome editing — or CRISPR, for short — is biotechnology tool that scientists can use to make changes to DNA at precise locations. Changing a DNA sequence in a living being is known as gene editing or genome editing.