Keywords
Abstract
Genetic engineering is changing medicine by allowing disease mechanisms to be addressed at the level of DNA and cellular function. CRISPR-Cas9 provides programmable targeting, while base editing and prime editing expand the range of possible genetic changes. This narrative review examines their biological principles, therapeutic applications, delivery strategies, and clinical limitations. Selected primary studies demonstrate substantial progress in sickle cell disease and transfusion-dependent beta-thalassemia, alongside early evidence in transthyretin amyloidosis, cancer immunotherapy, and an individually treated metabolic disorder. These applications differ in maturity and should not be interpreted as equally established treatments. Effective translation requires an appropriate genetic target, delivery to relevant cells, reproducible manufacturing, and durable clinical benefit. Genotoxicity, conditioning-related complications, affordability, and equitable access remain central considerations. The strongest prospects lie in matching the editing platform to the disease mechanism while evaluating patient outcomes rather than relying on editing efficiency alone.References
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