Next-Generation CRISPR Technologies and Their Applications in Gene and Cell Therapy

The emergence of clustered regularly interspaced short palindromic repeat (CRISPR) nucleases has transformed biotechnology by providing an easy, efficient, and versatile platform for editing DNA. However, traditional CRISPR-based technologies initiate editing by activating DNA double-strand break (DSB) repair pathways, which can cause adverse effects in cells and restrict certain therapeutic applications of the technology. To this end, several new CRISPR-based modalities have been developed that are capable of catalyzing editing without the requirement for a DSB. Here, we review three of these technologies: base editors, prime editors, and RNA-targeting CRISPR-associated protein (Cas)13 effectors. We discuss their strengths compared to traditional gene-modifying systems, we highlight their emerging therapeutic applications, and we examine challenges facing their safe and effective clinical implementation.