1. Introduction
CRISPR (Clustered Regularly
Interspaced Short Palindromic Repeats) is an
array of short repeated sequences separated by spacers with unique sequences. CRISPR
can be found on both chromosomal and plasmid DNA of bacteria. The spacers are
often derived from nucleic acid of viruses and plasmids, and are used as recognition
elements to find matching virus genomes and destroy them. These sequences play a key role in a bacterial immune system, and
form the basis of a genome editing technology known as CRISPR/Cas9 which allows
permanent modification of genes within organisms.


