Figure 2.

Mismatched sgRNA generates heritable mutants with Cas9 nuclease, but not with Cas9^D10A nickase. (A and B) Mutagenesis efficiency of sgRNAs and sgRNAs with mismatches (red). The mutagenesis efficiency of sgRNAs is tested in Cas9 or Cas9^D10A transgenic flies. Each row in (A) and (B) represents an sgRNA sequence and its mutagenesis rate. (A) Mutagenesis efficiency of white-G and a white-G derivative with two mismatches. (B) Mutagenesis efficiency of white-B and a white-B derivative with one mismatch. Very low mutagenesis efficiency (<0.1%) is detected with white-G and white-B when introduced into Cas9^D10A. Mismatched sgRNAs can introduce mutations when expressed in Cas9 flies, but not with Cas9^D10A nickase flies.