Gene therapy could be a way to fix a genetic problem at its source. By adding a corrected copy of a defective gene, gene therapy promises to help diseased tissues and organs work properly. This approach is different from traditional drug-based approaches, which may treat symptoms but not the underlying genetic problems.
Most commonly, gene therapy uses a vector, typically a virus, to deliver a gene to the cells where it's needed. Once it's inside, the cell's gene-reading machinery uses the information in the gene to build RNA and protein molecules. The proteins (or RNA) can then carry out their job in the cells.
But gene therapy is not a molecular bandage that will automatically fix any genetic problem. While many disorders or medical conditions can potentially be treated using gene therapy, others are not suitable for this approach. So what makes a condition a good candidate for gene therapy?