Skip to main content

Table 1 Comparison of CRISPR/Cas9, ZFNs, TALENs, meganucleases and RNAi

From: CRISPR/Cas9: the Jedi against the dark empire of diseases

  CRISPR/Cas9 ZFNs TALENs Meganucleases RNAi
Target site 19–22 bp 18–36 bp 24–40 bp 14–40 bp Target site should be located 50–100 nt from ATG
Retargeting possibility Easily retargeted without any complexity Yes, but requires complex molecular cloning Yes, but requires protein engineering Yes, by protein engineering Yes
Nuclease Cas9 FokI FokI I-SceI Dicer and Argonaute proteins
Recognition mechanism RNA-DNA Protein-DNA Protein-DNA Protein-DNA RNA
Targeting restrictions Protospacer adjacent motif (PAM) must be present Non-G-rich sequences are difficult to target T in the start and A at the end Novel sequences are difficult to target Only targets mRNA
Efficiency High High High High High
Limitations Off targets Both expensive and time consuming to construct Takes long to construct Limited versatility in targeting Off targets
Cytotoxicity Low Low Variable to high Low Variable to high
Multiplexing ease High Low Low Low High
Cost Low High Moderate Low Low