1Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK Correspondence: Matthew JA Wood, Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, OX1 3QX, UK. E-mail matthew.wood@dpag.ox.ac.uk The upregulation of specific genes in vivo has been an elusive goal for gene therapy when compared with the wide repertoire of methods avai...