Development and Therapeutic Applications of Precise Gene Editing Technology

精准基因编辑技术的发展及治疗应用

The advent of gene editing represents one of the most transformative breakthroughs in life science,making genome manipulation more accessible than ever before.While traditional CRISPR/Cas-based gene editing,which involves double-strand DNA breaks(DSBs),excels at gene disruption,it is less effective for accurate gene modification.The limitation arises because DSBs are primarily repaired via non-homologous end joining(NHEJ),which tends to introduce indels at the break site.While homology directed repair(HDR)can achieve precise editing when a donor DNA template is provided,the reliance on DSBs often results in unintended genome damage.HDR is restricted to specific cell cycle phases,limiting its application.Currently,gene editing has evolved to unprecedented levels of precision without relying on DSB and HDR.The development of innovative systems,such as base editing,prime editing,and CRISPR-associated transposases(CASTs),now allow for precise editing ranging from single nucleotides to large DNA fragments.Base editors(BEs)enable the direct conversion of one nucleotide to another,and prime editors(PEs)further expand gene editing capabilities by allowing for the insertion,deletion,or alteration of small DNA fragments.The CAST system,a recent innovation,allows for the precise insertion of large DNA fragments at specific genomic locations.In recent years,the optimization of these precise gene editing tools has led to significant improvements in editing efficiency,specificity,and versatility,with advancements such as the creation of base editors for nucleotide transversions,enhanced prime editing systems for more efficient and precise modifications,and refined CAST systems for targeted large DNA insertions,expanding the range of applications for these tools.Concurrently,these advances are complemented by significant improvements in in vivo delivery methods,which have paved the way for therapeutic application of precise gene editing tools.Effective delivery systems are critical for the success of gene therapies,and recent developments in both viral and non-viral vectors have improved the efficiency and safety of gene editing.For instance,adeno-associated viruses(AAVs)are widely used due to their high transfection efficiency and low immunogenicity,though challenges such as limited cargo capacity and potential for immune responses remain.Non-viral delivery systems,including lipid nanoparticles(LNPs),offer an alternative with lower immunogenicity and higher payload capacity,although their transfection efficiency can be lower.The therapeutic potential of these precise gene editing technologies is vast,particularly in treating genetic disorders.Preclinical studies have demonstrated the effectiveness of base editing in correcting genetic mutations responsible for diseases such as cardiomyopathy,liver disease,and hereditary hearing loss.These technologies promise to treat symptoms and potentially cure the underlying genetic causes of these conditions.Meanwhile,challenges remain,such as optimizing the safety and specificity of gene editing tools,improving delivery systems,and overcoming off-target effects,all of which are critical for their successful application in clinical settings.In summary,the continuous evolution of precise gene editing technologies,combined with advancements in delivery systems,is driving the field toward new therapeutic applications that can potentially transform the treatment of genetic disorders by targeting their root causes.

基因编辑技术是生命科学领域最具变革的突破性技术之一,它的出现使基因组的遗传操作变得极为便捷。传统的CRISPR/Cas基因编辑通过引发DNA双链断裂(DSB)发挥作用,特别适合基因失活的研究,但在基因的精准修饰方面略有不足。新的基因编辑技术可以不依赖DSB和同源重组修复(HDR),达到了前所未有的精准度,目前已经开发了包括碱基编辑、引导编辑和CRISPR相关转座酶(CAST)在内的多种编辑系统,实现了从单个核苷酸到DNA大片段范围内的精准编辑。近年来,这些精确基因编辑工具的优化大大提高了编辑的效率、特异性和多功能性,如能够实现颠换的碱基编辑器、更高效和精准的增强型引导编辑系统,以及用于大段DNA精确插入的CAST系统,极大扩展了这些工具的应用范围。同时,体内递送系统的持续发展也极大推动了精准基因编辑工具的治疗应用,有效的递送系统对于基因治疗的成功至关重要,近年来在病毒和非病毒载体方面的进展提高了体内基因编辑的有效性和安全性。精确基因编辑技术在治疗遗传性疾病方面潜力巨大,本综述讨论了精准基因编辑工具和递送系统的最新进展,及其在心肌病、肝病和听力疾病等遗传性疾病中的临床前治疗应用,也讨论了技术在安全性和特异性的优化、递送系统的改进等方面存在的挑战,凸显了其从根本上治愈疾病的巨大潜力。