CRISPR technology or CRISPR/Cas9 technology is a genome-editing tool derived from the bacterial defense system against viruses and plasmids. The system comprises the Cas9 nuclease enzyme to create site-directed dsDNA (double-stranded DNA) break and a guide RNA, which is a predesigned 20 bp long RNA sequence within a more extended RNA scaffold. This sequence guides the Cas9 enzyme to the target sequence to cut across both DNA strands. The CRISPR system varies among bacterial species depending on the structure and function. Presently, the system is mainly categorized into two classes (I and II) and six types (I–VI). Class I represents 90% of the CRISPR systems and inclu...
