A Mini Review on CRISPR -Cas: The Cutting Edge Of DNA Editing
Authors: Santra Chitta Ranjan 
Published: July 2021

The ability to control and modify DNA—the code of life, has long been cherished by the scientists. They want to use genome editing to investigate different diseases that affect humans. With this easier access to DNA sequences, scientists are on the verge of a third revolution
that will deeply impact our lives, to the extent that computers have changed society: we are entering the era of “gene editing”, following the era of “gene reading”. Gene editing is the rational and precise modification of DNA sequences program in living cells and organisms.
Nuclease-based gene editing is already widely used in research as a cost-effective, fast, and easy way to conduct genetic experiments. Other recent approaches to targeted genome modification – zinc-finger nucleases [ZFNs] and transcription-activator like effector nucleases [TALENs]–
enable researchers to generate permanent mutations by introducing double-stranded breaks to activate repair pathways. These approaches are costly and time-consuming to engineer, limiting their widespread use, particularly for large scale, high-throughput studies. A new gene editing technology
known as CRISPR-Cas9 offers the potential for substantial improvement over previous technologies in that it is simple to use and inexpensive and has a relatively high degree of precision and efficiency. These characteristics have led many in the scientific and business communities to assert
that CRISPR-Cas9 will lead to groundbreaking advances in many fields, including agriculture, energy, ecosystem conservation, and in the investigation, prevention, and treatment of diseases. The advent of facile genome engineering using the bacterial RNA-guided CRISPR-Cas9 system in animals
and plants is transforming biology. This article is an aim to understand CRISPR (CLUSTERED REGULARLY INTERSPACED PALINDROMIC REPEAT) biology from its initial discovery through the elucidation of the CRISPR-Cas9 enzyme mechanism, which has set the stage for remarkable developments using this
technology to modify, regulate, or mark genomic loci in a wide variety of cells and organisms from all three domains of life. CRISPR-Cas9 has triggered a revolution in which laboratories around the world are using the technology for innovative applications in biology. The power of this technology
to systematically analyze gene functions in mammalian cells, study genomic rearrangements and the progression of cancers or other diseases, and potentially correct genetic mutations responsible for inherited disorders. CRISPR-Cas9 is having a major impact on functional genomics conducted in
experimental systems. Its application in genome-wide studies will enable large-scale screening for drug targets and other phenotypes and will facilitate the generation of engineered animal models that will benefit pharmacological studies and the understanding of human diseases. CRISPR- Cas9
applications in plants and fungi also promise to change the pace and course of agricultural research. Future research directions to improve the technology will include engineering or identifying smaller Cas9 variants with distinct specificity that may be more amenable to delivery in human
cells. Understanding the homology- directed repair mechanisms that follow Cas9-mediated DNA cleavage will enhance.