This is the old version of CHOPCHOP.
The new CHOPCHOP is available at chopchop.cbu.uib.no


or paste input sequence

Target specific region of gene






Restrict targeting



Restriction enzymes


Method for determining off-targets in the genome:




5' requirements for gRNA:




PAM motif:




Distance between TALENs:

Size of TALENs:

Number of mismatches to search for when finding off-targets:

G repeat variable diresidue (RVD):



Product size:

Primer size:

Primer Tm:

Minimum distance from primer to target site:

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