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Frequently asked questions

Our Scientific Applications Support team has assembled a list of frequently asked questions to help you find answers quickly. Filter using one or more categories to focus on specific topics, or use the search bar to perform a text search.

Is the PAM sequence part of the CRISPR-Cas9 crRNA construct?

No. The PAM sequence is located on the non-complementary strand. That is, it is on the strand of DNA that contains the same DNA sequence as the target crRNA [1]. The PAM sequence should not be included in the design of the crRNA.

The most commonly used Cas9 nuclease, derived from S. pyogenes, recognizes a PAM sequence of NGG that is found directly downstream of the target sequence in the genomic DNA, on the non-target strand.

Want to Learn More?

Download The CRISPR Basics Handbook that covers applications of CRISPR technology from guide RNA design to data analysis.

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  1. Anders C, Niewoehner O, et al. (2014) Structural basis of PAM-dependent target DNA recognition by the Cas9 endonuclease. Nature. 513(7519):569–573.

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