Today, scientists recognize three categories of restriction enzymes: type I, which recognize specific DNA sequences but make their cut at seemingly random sites that can be as far as 1,000 base ...

Various types of endonucleases – enzymes that can cut DNA – were already known before CRISPR-Cas9. The discovery of restriction enzymes in the early 1970s heralded a new age in molecular biology.

Template fragments are generated by: (1) digestion of genomic DNA with a combination of the two restriction enzymes EcoRI and MseI (blue and red arrows represent EcoRI and MseI restriction enzyme ...