From bacteria to humans: The CRISPR/Cas9 editing system, a novel therapeutic

摘要

CRISPR (clustered regulatory interspaced short palindromic repeats) is a bacterial adaptive immune system, which can target specific sequences of foreign nucleic acids. The system is made up of unique spacer sequences flanked by short, repetitive, palindromic sequences, and sequences encoding Cas (CRISPR associated) proteins. The CRISPR-Cas9 system has been utilized from S. pyrogenes for use in eukaryotes for gene editing. Many years were spent uncovering the components of the system and its mechanism. Now the RNA-guided endonuclease abilities of the system are utilized to induce double-strand breaks in targeted DNA sequences. Through the advent of double-strand breaks researchers can now induce mutations, knock out genes through non-homologous end joining, and knock-in DNA sequences through homologous directed repair. Additionally, the system has been utilized in gene regulation to activate or repress protein expression.;Studies have shown that CRISPR-Cas9 as a gene-editing tool is highly efficient and specific. The system only requires a Cas9 protein and guideRNA to function and can alter multiple genes with the addition of different guideRNA. Most scientists have reported minimal off-target mutations caused by Cas9, and many strategies have been initiated to reduce off-target effects even further. Already, the system has been shown to have therapeutic applications both in vitro in human cells and in vivo in animals (including non-human primates). Future applications in therapeutics and gene-editing have the potential to change research and medicine.