It aims to restore the healthy function of cells by replacing or correcting the defective gene. Gene therapy can be used to replace an abnormal gene with a normal one, to insert a missing gene, to switch off rogue genes that may cause cancers and to stop viruses multiplying within cells. The modified cells and genes are not passed onto children. Certain technical obstacles are yet to be overcome if gene therapy is to deliver the expected benefits to treat human disease. Even the most advanced cell therapy techniques are still at the experimental stage in clinical trials.
Further research is needed to develop safe, reliable gene therapy techniques.