Genome Editing: A Safe Alternative to Genetic Engineering of Crops

Methods for genetic improvement of crops have evolved over the years, to be more efficient and precise. Genome editing, the latest tool for plant genetic improvement, consists of a set of techniques, employed to add, delete, alter, or replace fragments of DNA in a specific genome location in an organism, thereby changing its genetic information. The major genome-editing technologies comprising of zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the clustered regularly interspaced short palindromic repeats (CRISPR-Cas 9) nuclease systems are outlined with emphasis on CRISPR-Cas 9 system. Gene-editing technologies are used to decode the structure of genes and their functions, incorporate tolerance to abiotic and biotic stress factors, induction of male sterility, herbicide resistance, improvement of nutritional value, etc. This chapter briefly outlines the history, principles, and improvements of genome editing, compares various genome-editing tools and also genome editing with other genetic modification methods such as RNAi, and discusses strategies for genome editing in crops, applications, advantages, challenges or concerns, and prospects of genome editing. It also encompasses the rules and guidelines governing revolutionary genome-editing technologies.