Vectors for Gene Delivery

Gene therapy bases its rationale on the transfer of genetic components (genes or fragments thereof) into somatic cells, with the aim of preventing, correcting, or healing various types of disorders. After this introductory sentence you expect us to start telling you some of the marvellous achievements in setting up the tools that allow this transfer. However, before entering into the intricate details of vectorology please allow us the following clear-cut statement: “as of today there is no perfect or general vector for gene therapy and there won’t be probably any in the foreseeable future”. We hope that with this statement in mind, it will be easier for the readers to understand why there is still such a multitude of seemingly disparate efforts in establishing appropriate vehicles for the gene transfer. Therefore, the efficacy of gene therapy largely depends on the properties of the chosen ‘vector’ for gene transfer and expression. The reader should be also reminded that there is still some ambiguity in the denomination ‘vector’ because this concept can be understood either as the mere cis-elements that compose the transferred sequence (that is the nucleic acid sequence arrangement) or as the vehicle/method which is utilised for the transfer of the required gene. 1. PROBLEMS INFLUENCING VECTOR'S CHOICE