Table 1.

List of Cas9 modifications and its applications.

Modification		Engineering	Application	Reference
SpCas9n (Cas9n)		Substitution of aspartite to alanine (D10A) in the RuvC domain	Allows knock in via HDR	Cong et al., 2013
Dead cas9 (dcas9)		Cas9 nuclease inactivation and double nicking using nickase	Nicking enhances specificity	Mali et al., 2013
FokI Cas9 (fCas9)		Inactivated Cas9 nuclease fused with FokI nuclease	Increased on target activity	Guilinger et al., 2014