ABSTRACT
Medical genetics is a hybrid discipline, depending on the interaction between laboratory and clinical workers, but most of its key advances over the past half century have depended on laboratory discoveries. Cytogenetics was the first laboratory field to have practical applications; after the initial recognition of human chromosome abnormalities from 1959, a series of technical advances, most notably chromosome banding, saw it largely change from a research to a service area, usually linked with clinical genetics and stimulating this through the need for diagnostic interpretation and genetic counselling. Biochemical genetics also advanced but in Britain stayed less closely connected with medical genetics. From around 1980 human molecular genetics developed a major impact, pioneered by molecular analysis of the haemoglobin disorders, but then allowing the understanding, diagnosis and prediction of many other mendelian disorders, principally through the isolation of the genes involved through gene mapping and positional cloning. Important mendelian subsets of some common disorders, such as cancers, were found, and the close collaboration between molecular and clinical geneticists led to rapid development of molecular diagnostic services. During this time computing developments enabled the development of both laboratory and clinical databases, facilitating both research and service applications.
