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How are viral vectors used to deliver genes in gene therapy?

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CRISPR-Cas9; gene editing — gene editing The CRISPR-Cas9 gene-editing complex from the bacterium *Streptococcus pyogenes*.

In gene therapy, viral vectors serve as specialized delivery tools that leverage the natural ability of viruses to locate and enter target cells.1

To ensure safety, scientists modify these viruses by removing their original viral genes and replacing them with the specific genetic material intended for therapeutic use. Once the vector enters a host cell, the delivered gene may either integrate into the host's DNA or exist temporarily to express the desired protein. This process aims to repair mutations or provide functional gene products to treat conditions like cystic fibrosis or cancer.12

However, the use of viral vectors involves significant ethical and safety considerations. Because the procedure involves genetic manipulation, it raises concerns regarding unintended mutations, potential immune responses in patients, and the broader implications of genetic engineering. It is a fundamental ethical imperative that such medical interventions prioritize patient safety and rigorous scientific oversight to prevent harm, especially given the risks observed in clinical trials.2