Chapter 20 - Research Trends in Genetically Modified (GM) Plants

Abstract

Recent ground-breaking advancements in the field of biotechnology and synthetic biology have established a new platform for improving qualitative and quantitative traits in many of the economically important crops. Broad spectrum genetic variation is an essential prerequisite for developing elite germplasms/varieties and until now, the plant breeders were mainly focussed on induced mutagenesis (either by irradiation or chemical mediated induction) for enhancing natural variation in plants. However, their exploitation is often constrained due to a higher mutation rate. Therefore, in the past recent years, researchers with serendipitous mind across the globe have significantly impacted genetic engineering by developing some of the cutting-edge genome editing technologies like Zinc Finger Nucleases (ZFNs), Transcription Activators Like Effector Nucleases (TALENS) and most elemental Clustered Regulatory Interspaced Short Palindromic Repeats (CRISPR) associated protein (Cas) for basic science research. Development of ZFNs marks the inception of gene editing of target sequence leading to the development of chimeric genes to induce target mutagenesis; however, they are time consuming and much costlier to develop. TALENs offers a much more comfortable/simpler approach for inducing target mutagenesis compared to ZFNs but are much more prone to homologous recombination resulting in off target generation of random insertion and deletions (INDELs). CRISPR Cas9 system has emerged as an indispensable tool that has revolutionized the way of genome editing in the field of agricultural biotechnology. Here in this chapter, we will present an overview of gene editing tools and describe their possible application for the rewiring of transgenic crops with advanced agronomic traits.