Broad Targeting Specificity during Bacterial Type III CRISPR-Cas Immunity Constrains Viral Escape (Cell Host & Microbe)

Exploring the target specificity of type III-A CRISPR-Cas systems, Pyenson et al. find that most point mutations in the target region still allow robust immunity. As a consequence, viral escape from the type III-A CRISPR-Cas immune response requires the full deletion of the target, which is a very rare event.