Introduction

The continuing development of genetics has profound implications for the future of medicine. Since the first edition of this book appeared in 2001, there have been important advances in understanding some of the genetic factors in common disorders. Much genetic research (‘genomic epidemiology’) is intended to lead to a better understanding of biological mechanisms such as immunity, which will help to understand disease progression. An example would be research in malaria, using genetic variation in populations as a way into understanding mechanisms which may prove helpful in the development of a vaccine. In the medium to longer term, the impact is perhaps most likely to be felt in the development of more effective treatments for the major diseases, including the use of medicines tailored to fit an individual's own genetic profile (‘pharmacogenetics’). Cheap and accurate sequencing techniques may conceivably allow everyone to know the full contents of their own genome, but that could be a double-edged sword, increasing the ethical, legal and social risks of genetic testing (Robertson, 2003).

What are these risks? And what are the practical ethical questions raised by genetics today? You have already encountered some of these issues in the previous chapter: for example, preimplantation genetic diagnosis. Here in Chapter 3 we will concentrate on the wider clinical aspects of genetics, outside the area of new reproductive technologies.