In recent years, CRISPR-Cas9 technology is widely acknowledged for having major applications in the field of biotechnology for editing genome of any organism to treat a variety of complex diseases and for other purposes. The acronym 'CRISPR-Cas' stands for clustered regularly interspaced short palindromic repeats-CRISPR-associated genes. This genetic organization exists in prokaryotic organisms and aids in the development of adaptive immunity since a protein called Cas9 nuclease cleaves specific target nucleic acid sequences from foreign invaders and destroys them. This mode of action has gained interest of the researchers to understand the insights of CRISPR-Cas9 technology. Here, we review that CRISPR-Cas organization is restricted to two classes and possesses different protein effectors. We also review the architecture of CRISPR loci, mechanism involved in genome editing by CRISPR-Cas9 technology and pathways of repairing double-strand breaks (DSBs) generated during the process of genome editing. This review also presents the strategies to increase the Cas9 specificity and reduce off-target activity to achieve accurate genome editing. Further, this review provides information on CRISPR tools used for genome editing, databases that are required for storing data on loci, strategies for delivering CRISPR-Cas9 to cells under study and applications of CRISPR-Cas9 to various fields. Safety measures are implemented on this technology to avoid misuse or ethical issues. We also discuss about the future aspects and potential applications of CRISPR-Cas9 technology required mainly for the treatment of dreadful diseases, crop improvement as well as genetic improvement in human.

中文翻译：

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使用CRISPR-Cas9技术进行基因组编辑一目了然。

近年来，CRISPR-Cas9技术在生物技术领域具有重要应用，可编辑任何生物的基因组以治疗多种复杂疾病并用于其他用途，因此被广泛认可。首字母缩写词“ CRISPR-Cas”代表成簇的规则间隔的短回文重复序列-CRISPR相关基因。这种遗传组织存在于原核生物中，并有助于发展适应性免疫，因为一种称为Cas9核酸酶的蛋白质会切割外来入侵者的特定靶核酸序列并将其破坏。这种作用方式引起了研究人员的兴趣，以了解CRISPR-Cas9技术的见解。在这里，我们回顾了CRISPR-Cas组织仅限于两类，并拥有不同的蛋白质效应子。我们还回顾了CRISPR基因座的体系结构，CRISPR-Cas9技术参与基因组编辑的机制以及修复基因组编辑过程中产生的双链断裂（DSB）的途径。这篇综述还提出了提高Cas9特异性并减少脱靶活性以实现准确的基因组编辑的策略。此外，本综述提供了有关用于基因组编辑的CRISPR工具，在基因座上存储数据所需的数据库，将CRISPR-Cas9递送至正在研究的细胞的策略以及CRISPR-Cas9在各个领域的应用的信息。对此技术实施了安全措施，以避免滥用或道德问题。我们还讨论了CRISPR-Cas9技术的未来方面和潜在应用，这些技术主要用于治疗可怕疾病，作物改良以及人类遗传改良。