Research Advances in CRISPR Technologies Independent of DNA Double-Strand Breaks

doi:10.3870/j.issn.1672-8009.2026.05.015

Abstract

Abstract: Gene editing technology can precisely modify specific DNA segments in the genome of an organism, opening up new ways for disease treatment, gene function research, gene testing and drug development. Conventional CRISPR-Cas9 gene editing relies on DNA double-strand break（DSB）, whose repair processes are prone to inducing indel mutations, exhibit cytotoxicity, and demonstrate low efficiency in homology-directed repair, significantly limiting its applications in precision medicine. To overcome this limitation, a series of novel CRISPR-derived technologies independent of DSB have emerged. This review systematically summarizes the principles, development, and applications of three representative technologies： base editors, prime editors, and transposon-based editors, with a focus on analyzing how their mechanistic innovations circumvent DSB. It further explores their respective advantages and inherent limitations in terms of editing efficiency, precision, target scope, and delivery challenges. Finally, the review offers perspectives on future technological directions, highlighting that editor miniaturization, efficiency enhancement, and delivery tool innovation are key to advancing clinical translation in this field.

Key words: CRISPR-Cas9, base editors, prime editors, transposon-associated editors

CLC Number:

WANG Ruihan, SUI Xianxian, YAN Yufeng. Research Advances in CRISPR Technologies Independent of DNA Double-Strand Breaks[J]. Journal of Medical Molecular Biology, 2026, 23(5): 592-599.

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