CRISPR-Based Genome Editing and Delivery Systems: Advances, Challenges and Future Directions

Abstract

Gene therapy and genome editing technologies have advanced significantly in recent decades and have shown great potential for treating inherited and acquired diseases. CRISPR-Cas is one of several genome editing tools currently being studied and has gained widespread popularity due to its ease of use, versatility, and relatively high efficiency compared to previous methods. This chapter provides an overview of major genome editing technologies, including previously developed tools such as zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs), as well as CRISPR-Cas systems such as Cas9, Cas12, and Cas13. The basic mechanisms underlying how these systems work, including target identification, DNA cutting, and cellular repair mechanisms following genome editing, are also discussed. The emphasis is also made on the newer editing techniques such as base editing, prime editing, and epigenome editing. These methods allow for more precise genome editing with minimal genome damage. In addition, since delivery remains one of the most important factors for successful genome editing, viral and non-viral delivery strategies are discussed, including the advantages and limitations of adeno-associated viruses, adenoviruses, lentiviruses, lipid nanoparticles, polymers, and physical delivery. While tremendous advancements have been made in genome editing, there are still challenges that need to be addressed. These include off-target effects, immune responses, delivery challenges, and long-term safety. This chapter further outlines recent advancements and future directions for genome editing, including increased specificity, miniaturized editing platforms, artificial intelligence, and delivery.