Gene Therapy
A medical technique that treats disease by altering or replacing a patient's genes. Approved therapies now exist for several previously fatal genetic disorders.
Gene therapy treats disease by introducing, replacing, silencing, or editing genes within a patient's cells. Most current gene therapies use viral vectors — modified viruses that deliver functional gene copies — to compensate for faulty inherited genes.
After decades of setbacks, gene therapy reached the clinic in the 2010s. FDA-approved therapies now exist for spinal muscular atrophy (Zolgensma), inherited blindness (Luxturna), sickle cell disease and beta-thalassemia (Casgevy), and several haemophilias. Single-dose treatments often cost $1-3 million.
Gene therapy differs from CRISPR gene editing (which directly modifies DNA) but they're increasingly used together. Most therapies target somatic cells (body cells) rather than germline cells, so changes are not inherited.