Fundamental research in molecular biology: its relevance to medicine

Any research which has shed light on the nature of disease or opened new ways to its prevention or cure is here termed relevant, and the question will be asked whether the research could have been planned with these aims in mind. Examples will be taken from the chemistry and X-ray analysis of proteins and from molecular genetics. Blow and Hartley determined the amino acid sequence and atomic structure of the digestive enzyme chymotrypsin in order to solve the problem of enzymic catalysis. They succeeded but what they found has proved to be of much wider improtance than could have been foreseen at the outset: it gives the key to the mechanism of blood clotting and suggests new methods for its control. X-ray analysis of haemoglobin was started at a time when the structure of proteins was regarded as the central problem of biology, but it did not seem likely then that the results would shed light on the molecular pathology of inherited diseases. Ames made a life-long study of the genetic control of histidine biosynthesis in Salmonella because it represents an example of a widely used biological mechanism, but without expecting it to have any practical applications. Yet his recent exploitation of the system for the rapid and sensitive detection of chemical carcinogens may represent a breakthrough in cancer prevention. This unpredictable relationship of molecular biology to medicine is symptomatic of the subject's youth.