Over the past few years, genetics research has been in a phase of remarkably sustained and continuous revolution. The advent of "new genetics" of recombinant DNA has resulted in new discoveries occurring at a breath taking pace, many of which have important clinical implications, for example, in new approaches to the diagnosis and treatment of hemoglobinopathies, cystic fibrosis and some forms of muscular dystrophies. Recent findings of psychiatric relevance have included the localization of the genes for Huntington's chorea and the use of DNA probes in predictive testing. Advances have been...