INTRODUCTION

The completion of the Human Genome Project has been heralded as one of the major landmark events in science. The human genome contains the blueprint for human development and maintenance and may ultimately provide the means to understand human cellular and molecular processes in both health and disease. The genome is the full complement of DNA from an organism and carries all the information needed to specify the structure of every protein the cell can produce. The realisation that DNA lies behind all of the cell's activities led to the development of what is termed molecular biology. Rather than a discrete area of biosciences, molecular biology is now accepted as a very important means of understanding and describing complex biological processes. The development of methods and techniques for studying processes at the molecular level has led to new and powerful ways of isolating, analysing, manipulating and exploiting nucleic acids. Moreover, to keep pace with the explosion in biological information a new area termed bioinformatics has evolved and provides a vital role in current biosciences. The completion of the Human Genome Project and numerous other genome projects has allowed the continued development of new exciting areas of biological sciences such as biotechnology, genome mapping, molecular medicine and gene therapy.

In considering the potential utility of molecular biological techniques it is important to understand the basic structure of nucleic acids and gain an appreciation of how this dictates the function in vivo and in vitro.