Table 1 Comparison of TALEN and CRISPR-Cas9 systems
TALEN | |
Advantages | Disadvantages |
~30Â bp target requirement results in less off-target effects | Difficult protein engineering potentially increases time and financial investment |
No PAM requirement; can target any sequence | Efficiency varies for each construct |
Cannot target methylated DNA | |
Difficult to engineer nickase | |
CRISPR-Cas9 | |
Advantages | Disadvantages |
Able to multiplex | Higher potential for off-target effects |
Easy to engineer | PAM requirement limits target |
Can target methylated DNA | |
Easy to create a nickase | |