In recent years, the number of tools and techniques that enable genetic material to be added, removed or altered at specific locations in the genome has increased significantly. The objective is to know the structure of genomes, the function of genes and improve gene therapy.

In this work we intend to explain the functioning of the CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated protein 9) and the advantages that this technique may have compared to previously developed techniques, such as RNA interference (RNAi), Zinc Finger Nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs) in gene and genome editing.

We will start with the story of the discovery, then its biological function in the adaptive immune system of bacteria against bacteriophage attack, and ending with a description of the mechanism of action and its use in gene editing. We will also discuss other Cas enzymes with great potential for use in genome editing as an alternative to Cas9.

CRISPR/Cas9 is a simple, inexpensive, and effective technique for gene editing with multiple applications from the development of functional genomics and epigenetics. This technique will, in the near future, have great applications in the development of cell models for use in medical and pharmaceutical processes, in targeted therapy, and improvement of agricultural and environmental species.

近年来，能够在基因组特定位置添加、去除或改变遗传物质的工具和技术的数量显着增加。目的是了解基因组的结构、基因的功能并改进基因治疗。

在这项工作中，我们打算解释 CRISPR/Cas9（成簇规则间隔短回文重复序列/CRISPR 相关蛋白 9）的功能以及该技术与先前开发的技术（例如 RNA 干扰 (RNAi)、锌）相比可能具有的优势。基因和基因组编辑中的指状核酸酶 (ZFN) 和转录激活子样效应核酸酶 (TALEN)。

我们将从这一发现的故事开始，然后是它在细菌适应性免疫系统中抵抗噬菌体攻击的生物学功能，最后描述其作用机制及其在基因编辑中的应用。我们还将讨论其他具有巨大潜力的 Cas 酶，可作为 Cas9 的替代品，用于基因组编辑。

CRISPR/Cas9 是一种简单、廉价且有效的基因编辑技术，在功能基因组学和表观遗传学的发展中具有多种应用。在不久的将来，这项技术将在开发用于医疗和制药过程、靶向治疗以及农业和环境物种改良的细胞模型方面具有巨大的应用。