Gene therapy concept render

Gene therapy is a technique that modifies genes to treat or prevent diseases, using viral vectors or CRISPR to correct mutations.

About this subject

Gene therapy represents a revolutionary frontier in molecular medicine, allowing the correction of genetic defects at their source. Unlike conventional treatments that alleviate symptoms, this approach acts on the DNA of cells, introducing, removing, or altering genetic segments. Early clinical attempts in the 1990s faced safety and efficacy challenges, but recent advances in adeno-associated viral vectors and CRISPR-Cas9 technology have yielded promising results.

Hereditary diseases such as cystic fibrosis, Duchenne muscular dystrophy, and certain types of inherited blindness are prime targets. In 2017, the FDA approved tisagenlecleucel (Kymriah), an ex vivo gene therapy for acute lymphoblastic leukemia, where a patient's T cells are genetically modified to recognize and attack cancer cells. Other products like Luxturna for Leber congenital amaurosis have demonstrated that gene therapy can restore vision in children.

The technique often uses inactivated viruses as vehicles to deliver functional genes. However, a non-viral alternative, such as CRISPR gene editing, enables precise cuts in DNA to insert or repair sequences. Somatic (non-heritable) editing is the most practiced, while germline editing remains ethically debated. High costs and the need for specialized infrastructure limit access, but research aims to make these therapies more affordable worldwide.

Frequently Asked Questions

What diseases can be treated with gene therapy?

Currently, gene therapy is used for hereditary diseases such as cystic fibrosis, muscular dystrophy, some forms of blindness, and certain cancers like leukemia. Clinical trials are also ongoing for hemophilia, sickle cell disease, and neurodegenerative disorders.

Can gene therapy alter the DNA of descendants?

Somatic gene therapy, the most common, affects only the treated patient's cells and is not passed to offspring. Germline editing, which would alter eggs, sperm, or embryos, is still prohibited in many countries due to ethical and safety concerns.

What are the risks of gene therapy?

Risks include adverse immune reactions, insertion of the gene in the wrong location in the genome (potentially causing cancer), and side effects from viral vectors. However, newer technologies like CRISPR aim to minimize these risks with greater precision.