CRISPR guide RNAs program Cas9 nuclease to cut genomic DNA at a specific location. Once the double-strand break (DSB) occurs, the mammalian cell utilizes endogenous mechanisms to repair the DSB. In the presence of a donor DNA, either a ssDNA oligo or a plasmid donor, the DSB can be repaired precisely using HDR resulting in a desired genomic alteration (insertion, removal, or replacement).

Get started with designing HDR donor templates

  • CRISPR Design Tool

    Place a custom guide RNA order, or design and order your own synthetic sgRNA, crRNA, or lentiviral sgRNA with our easy-to-use interface.

  • HDR Donor Designer

    Design and order a custom donor oligo or plasmid for HDR-mediated gene editing in over 30 different species