Research Progress on CRISPR/Cas9 Mediated Genome Editing

Clustered regularly interspaced short palindromic repeats(CRISPR)and CRISPR-associated protein 9(Cas9)constituted the CRISPR/Cas9 genome editing system,which provides a more efficient way for gene targeting than zinc finger endonuclease(ZFN)and transcription activator-like effector nuclease(TALEN).It is becoming a hot spot in the field of genome editing,and successfully applied to gene targeting of bacteria,human cells,zebra fish,mouse,pig,cynomolgus monkey and several plants.However,the high off-target rate and poor specificity of CRISPR/Cas9 technology hindered its application in medical treatment.Here,the research progress in the structure,classification,function,and mechanism of the CRISPR/Cas9 system is reviewed.