“After pioneering studies demonstrated the editing of zebrafish genome with long dsDNA (Bedell et al., 2012; Zu et al., 2013), several studies reported the insertion of large DNA fragments at defined zebrafish gene loci via DSB-mediated HR (Hisano et al., 2015; Hoshijima et al., 2016; Shin et al., 2014; Zu et al., 2013) or homology-independent repair mechanisms (Auer et al., 2014; Kimura et al., 2014; Li et al., 2015). […] Although we could not efficiently induce DSBs in the shha intronic sequence using the CRISPR/Cas9 system, this approach may be useful for targeting Zwitch into other genes.”