GENE THERAPY DEFINED AND EXPLAINED

Gene therapy is an experimental technique that aims to treat or prevent disease by altering the genetic makeup of cells. The basic premise involves introducing genetic material into a patient’s cells and tissues to elicit a therapeutic effect. Scientists have been studying gene therapy for over 30 years in hopes of developing treatments for cancers, genetic disorders, viral infections and other complex diseases that conventional drugs struggle to address effectively.

Current gene therapies can work by several mechanisms. Most treatments involve replacing a mutated, disease-causing gene with a healthy copy of that gene in order to restore normal function. Other approaches focus on inactivating or “knocking out” problematic genes rather than replacing them. The practice can also encourage the production of defective proteins or introduce new genes to help the body fight disease in different ways.

While early gene therapy research focused on monogenic diseases caused by defects in a single gene, scientists now aim to develop treatments that target polygenic disorders too. These include heart disease, diabetes and Alzheimer’s disease where variants in multiple genes contribute to disease risk. Advances in viral vector design, gene editing and delivery techniques have greatly expanded the possibilities over the past decade.

To deliver gene therapies, scientists often rely on disarmed versions of viruses. These vectors act as biological delivery trucks to carry therapeutic genes directly into human cells. The viral genes are first removed though, preventing virus replication and minimizing safety risks. Once inside cells, the functional gene cargo integrates with human DNA to exert its intended effects.

Over 2,900 gene therapy clinical trials are completed, underway or approved worldwide. In the United States, the Food and Drug Administration has so far approved gene therapies for certain cancers, blindness, spinal muscular atrophy and other rare diseases. The approval of CAR T-cell therapy for certain blood cancers in 2017 marked an important milestone for the field.

Nonetheless significant scientific hurdles around safety and efficacy remain. Also, ethical concerns persist around germline gene editing that can pass changes on to future generations. Still, the overall momentum behind gene therapy continues to build with the wider genomics revolution in biomedicine. Proponents believe gene therapy coupled with precision diagnostics represents the future of sustainable, cost-effective management for some of society’s most intractable diseases.