BharatNotes What is Gene Therapy?
Gene therapy is the administration of genetic material to modify or manipulate the expression of a gene, or to alter the biological properties of living cells, for therapeutic benefit (US FDA). Rather than treating symptoms, it targets the genetic root of disease. The three core strategies are: replacing a disease-causing gene with a healthy copy, inactivating a malfunctioning gene, and introducing a new or modified gene to help the body fight or treat a condition.
Key Types and Delivery Methods
Gene therapy is classified along two axes:
| Basis | Categories | Key point |
|---|---|---|
| Cell type targeted | Somatic vs germline | Somatic (non-reproductive) changes are not inherited; germline edits pass to offspring and remain ethically prohibited worldwide |
| Site of modification | In vivo vs ex vivo | In vivo: genetic material delivered directly into the body; ex vivo: cells modified in the lab, then reinfused |
Delivery usually relies on engineered viral vectors. Adeno-associated virus (AAV) is favoured for in vivo delivery (e.g., the brain-targeted therapy Kebilidi, FDA accelerated approval Nov 2024), while lentiviral vectors, which integrate stably and infect non-dividing cells, are preferred for ex vivo work such as CAR-T manufacturing. Gene-editing tools like CRISPR-Cas9 have made the field faster and more precise.
Significance and Current Status
Milestones (as of June 2026):
- 1990 — First human gene therapy trial (Ashanti DeSilva, ADA-SCID), using a retroviral vector.
- Nov 2012 — Glybera (alipogene tiparvovec) became the first gene therapy approved in the EU.
- Dec 2023 — FDA approved Casgevy, the world's first CRISPR/Cas9-based medicine, for sickle cell disease (patients aged 12+ with recurrent vaso-occlusive crises); Lyfgenia was approved alongside it.
- Oct 2023 — India's CDSCO approved NexCAR19, the country's first indigenous CD19-targeted CAR-T therapy for B-cell lymphomas and leukaemia, developed by ImmunoACT (incubated at IIT Bombay).
NexCAR19 is strategically important for affordability: priced at roughly USD 50,000, against USD ~400,000-500,000 for comparable CAR-T therapies in the US and Europe (industry estimates, 2023-24). This positions India in the global advanced cell-and-gene therapy market while widening access.
UPSC Angle
The topic blends pure science (vectors, CRISPR, somatic vs germline) with policy and ethics. For Prelims, master the definitions and the India-specific firsts (NexCAR19). For Mains GS3, frame it around indigenous biotech capacity, healthcare affordability, and regulation by CDSCO; for GS4, the germline-editing ban is a ready bioethics case study. Cross-link with current affairs on Ujiyari.com for the latest approvals, as the regulatory landscape evolves rapidly. This is a foundation concept underpinning broader questions on biotechnology and emerging technologies.
