CRISPR–Cas Systems in Human Disease Therapy: Advances, Clinical Applications, Limitations, and Future Directions

CRISPR-Cas systems have emerged as versatile platforms for targeted genome and transcriptome engineering, enabling precise manipulation of disease-associated genetic pathways. Continued advances in CRISPR technologies including base editing, prime editing, and epigenome modulation have expanded therapeutic possibilities beyond nuclease-mediated DNA cleavage, allowing programmable gene correction and regulation. Early clinical studies demonstrate sustained therapeutic benefit in selected monogenic disorders and highlight the feasibility of both ex vivo and in vivo editing strategies. However, clinical translation remains constrained by challenges such as off-target activity, delivery inefficiency, immune responses to Cas proteins, editing heterogeneity, and uncertainties regarding long-term safety. This review critically synthesizes recent advances in CRISPR-Cas systems for human disease therapy, integrating molecular innovations, delivery strategies, clinical progress, and ethical considerations. By evaluating both technological achievements and unresolved limitations, this article outlines key priorities for advancing CRISPR-based therapeutics toward safe, effective, and equitable precision medicine.