The version of Cas9 used in prime editing has one of its two nuclease domains deactivated, turning it into a “nickase” that will only cut one of the DNA strands, rather than both. So, once the pegRNA ...

A CRISPR Cas9 nickase protein makes a single-strand DNA nick, and then a base-converting enzyme, physically attached to Cas9, makes a cytosine-to-thymine switch. We typically deliver base editors ...

CRISPR-Cas9 genome editing exploits the CRISPR-Cas system to modify a genome in a targeted manner. Guided by RNA, the Cas9 endonuclease breaks DNA at a target sequence. Imprecise repair of the ...

Prime editors are a kind of fusion proteins between a Streptococcus pyogenes Cas9 (SpCas9) H840A nickase mutant and an engineered reverse transcriptase (RT) domain. The pegRNA functions as both ...

The recent approval of a CRISPR-Cas9 therapy for sickle cell disease ... which has multiple active parts, including a nickase -; an enzyme that binds and nicks double-stranded DNA -; and reverse ...