In recent years, there has been a revolution in how medical diagnosis is carried out. The Human Genome Project has offered new ways of screening for diseases and our understanding of the molecular basis of cancer, infectious disease and inherited disease has helped to develop new therapies. For instance, although more needs to be done, there has been a dramatic rise in the survival rates for all cancers and huge strides have been made in our understanding of how this disease develops. As we begin to understand, we can begin to develop new treatments.

Scientists are also developing new ways of testing for disease. With the availability of genetic tests, we have a chance to screen out many diseases that have occurred for many thousands of years. Some of these, such as Sickle Cell Anemia, may have given humanity an advantage through improved resistance to malaria in the past. But now they pose a problem themselves. We can screen for these diseases in children and adults, in the womb before birth, or even in vitro before embryo implantation. These tests offer great hope and promise but raise huge ethical, social and moral issues for society.

Thus, the revolution in our understanding of disease offers improvements in diagnosis leading to more accurate treatments and improved quality of life but the science needs to be understood in the wider social context.