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In the current scenario, CRISPR‐Cas9 is a widely adopted genome edited system (GET) due to simplicity, efficiency and versatility. In 1987, CRISPR array was identified in Escherichia coli (E. coli) genome (Ishino et al. 1987) with unknown biological properties. During 2005, several studies were successful that revealed a CRISPR array role in adaptive immunity based on the availability of homologs spacers to viral and plasmid sequence (Pourcel et al. 2005). Jinek et al. (Jinek et al. 2012) first reported an RNA‐guided DNA cleavage system with high required target efficiency. Deltcheva et al. (Deltcheva et al. 2011), uncovered CRISPR array provides protection against foreign DNA when coupled with Cas9 protein whereas, the immune system was based on RNA mediated DNA targeting. CRISPR/Cas systems are part of the adaptive immune system of bacteria and archaea, protecting them against invading nucleic acids (spacers) such as viruses by cleaving foreign DNA in a sequence dependent manner. The immunity is obtained via integration of spacers between two adjacent repeats at the proximal end of a CRISPR locus. The spacers are transcribed into CRISPR RNAs (crRNAs) approximately 40 nt in length by successive encounters with foreign DNA, and combines with trans activating CRISPR RNA (tracrRNA) to activate and guide Cas9 nuclease (Barrangou et al. 2007). The Cas9 cleaves the homologs double‐stranded DNA sequence (protospacer) in the foreign DNA. The availability of PAM downstream of the target DNA is a key for the successful cleavage with frequent 5′‐NGG‐3′ and less frequent 5′‐NAG‐3′ (Hsu et al. 2013). Seed sequence approximately 12 bp upstream of the PAM are integral for pairing between RNA and target DNA (Bortesi and Fischer 2015). Multiplex editing by the introduction of double‐stranded breaks (DSBs) on various sites and ability to edit several genes at the same time is a unique feature of CRISPR/Cas system (Zhou et al. 2014). It only requires monomeric Cas9 protein with sequence‐specific gRNA meanwhile, ZFNs and TALENs requires dimeric proteins with reference to target site. In the CRISPR/Cas system, the recognition of target site is based on the Watson and Crick model enabling the off‐target detection through sequencing analysis along with off‐target mutation can be fixed by careful design of gRNA. On the contrary, ZFNs and TALENs target specificity depends on protein‐DNA interaction with unpredictable and function‐specific properties (Cho et al. 2014). Moreover, the scientific community equipped with CRISPR expertise had contributed a lot to disseminate the fresh information to newcomers which is opposite to ZFN proprietary nature. Several online platforms are now available and are assisting researchers for all concerns related to CRISPR (Table 3.1; Figure 3.1).