1. ¹Nuffield Department of Clinical Laboratory Sciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
2. ²The UK Cystic Fibrosis Gene Therapy Consortium

Correspondence: Dr SC Hyde, Nuffield Department of Clinical Laboratory Sciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK. E-mail: steve.hyde@ndcls.ox.ac.uk

Received 9 October 2008; Revised 1 December 2008; Accepted 1 December 2008; Published online 8 January 2009.

Abstract

Plasmid DNA (pDNA) expression vectors are fundamental to all forms of non-viral gene transfer. In this review, we discuss principles of pDNA design and production including the impact of bacterially derived sequences on transgene expression and minicircle approaches to minimize their effects. The impact of inclusion of DNA elements such as scaffold matrix attachment regions (S/MARs), transcription factor (TF)-binding sites and tissue-specific promoters are described. The benefits of eliminating CG dinucleotides (CpGs) from the pDNA are also considered.