Option 1 (2-part guide RNA)
All Alt-R CRISPR-Cas9 crRNAs are 35–36 nt RNA oligos containing the 19 or 20 nt target-specific protospacer region, along with the 16 nt tracrRNA fusion domain. We recommend 20 nt protospacers for most applications. crRNAs must be duplexed with
Alt-R CRISPR-Cas9 tracrRNA before RNP complex formation.
Alt-R CRISPR-Cas9 crRNAs are synthesized with proprietary chemical modifications, which protect the crRNA from degradation by cellular RNases and further improve on-target editing performance. When using 2-part gRNAs under highly challenging conditions
(e.g., high nuclease environments or with Cas9 mRNA), use Alt-R CRISPR-Cas9 crRNA XT, which have additional chemical modifications for the highest level of stability and performance.
We guarantee* our predesigned guide RNAs targeting human, mouse, rat, zebrafish, or nematode genes. For other species, you may use our proprietary algorithms to design custom guide RNAs. If you have protospacer designs of your own or from publications,
use our design checker tool to assess their on- and off-targeting potential before ordering guide RNAs that are synthesized using our Alt-R guide RNA modifications.