CRISPR-Cas: From bacterial immunity to precision genome engineering

The CRISPR-Cas system is an adaptive immune strategy in bacteria that has rapidly transformed into a cornerstone of modern genome engineering with broad applications in medicine, agriculture, and biotechnology. This review explores its molecular foundations and highlights its expanding functional scope, including roles in immunity, DNA repair, and transcriptional regulation. CRISPR technology has emerged as a powerful tool in addressing major global health challenges, enabling precise genome modifications in drug-resistant parasites such as Plasmodium and Trypanosoma cruzi, as well as offering promising strategies against persistent viral infections like HIV and hepatitis B. However, challenges remain, particularly the risk of off-target effects, which underscores the need for refined precision tools and innovative delivery methods. Recent advances are addressing these limitations through next-generation approaches such as engineered virus-like particles, DNA nanostructures, and synthetic exosomes are improving delivery efficiency and targeting specificity, while bioresponsive hydrogels offer controlled, site-specific release of editing components. At the same time, newer tools like prime editing systems and Cas12 variants are achieving highly accurate, double-strand break–free modifications with expanded targeting capacity. These advances point toward a safer, more adaptable future for genome editing. CRISPR's transformative impact will depend on improving delivery strategies, enhancing precision, and establishing robust ethical and regulatory frameworks. As applications expand, particularly in germline editing, ethical concerns surrounding intergenerational consent, human enhancement, and potential eugenic misuse become increasingly pressing. The possibility of non-therapeutic genetic modification further elevates the need for equitable access and strong global oversight to avoid deepening health disparities. The future of CRISPR lies in harmonizing scientific innovation with societal responsibility—ensuring that progress is both impactful and ethically grounded.