Development of clustered regularly interspaced short palindromic repeats/CRISPR-associated technology for potential clinical applications

Table 1 Features of clustered regularly interspaced short palindromic repeats/CRISPR-associated system

CRISPR type		Specific cleavage	Collateral cleavage	Secondary messenger	CRISPR inhibitors	Ref.
Class 1	I (Cas8)	DNA	Not identified to date	Not identified to date	Yes	[4]
	III (Cas10)	RNA	RNA, ssDNA	cOA	Not identified to date	[6-8]
	IV (Csf1)	Not studied yet	Not studied yet	Not studied yet	Not studied yet	[16]
Class 2	II (Cas9)	DNA	Not identified to date	Not identified to date	Yes	[4,5,16-20]
	V (Cas12, Cas14)	DNA	ssDNA	Not identified to date	Yes	[21-23]
	VI (Cas13)	RNA	RNA	Not identified to date	Not identified to date	[24-26]

CRISPR: Clustered regularly interspaced short palindromic repeats; ssDNA: Single-stranded DNA; cOA: Cyclic oligoadenylate.