PAM
Definition
A short DNA sequence that must sit next to the target site for a CRISPR enzyme to cut — a constraint you cannot design away.
Cas9 will not cut unless it finds its PAM immediately downstream of the target. In practice this means not every position in a genome is editable with a given enzyme, and choosing a target is partly a search for a nearby PAM.
Where this comes up
Articles that define pam in context.
