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What safety problems have occurred in gene therapy clinical trials?
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genetic engineering
The generation of vaccines relies heavily on techniques in genetic engineering.
Clinical trials for gene therapy have demonstrated significant risks, highlighting the complexity of using viral vectors to deliver genetic material. While these vectors are typically disabled to prevent replication, they can still trigger harmful immune responses in patients.1
Specific safety incidents include:
- Fatal Immune Response: In 1999, an American teenager named Jesse Gelsinger died after participating in a gene therapy clinical trial.1
- Leukemia-like Illness: In a 2000 study involving infants with X-linked severe combined immunodeficiency (XSCID), two of the 11 treated patients developed a leukemia-like illness.1
- Insertional Mutagenesis: A fundamental risk exists when a normal gene integrates into a host cell's genome. If the gene inserts into a functional gene rather than the intended site, it can cause a new mutation, potentially disrupting normal cellular processes.12
These outcomes underscore the critical importance of rigorous safety testing and the ongoing development of more precise delivery systems, such as nanoparticles, to minimize unintended biological consequences.1