sion through the aging process. Careful study of environmentalgenetic interactions throughout life is required.
Clearly, aging is a unique frontier of the life sciences that requires examination by a wide array of scientific disciplines. Research in aging will clarify the basis of many specific disorders of human aging and, in so doing, will add to the proud advances that have eliminated so many diseases of children and younger adults. Moreover, the ability to understand aging requires a powerful intellectual synthesis of diverse research areas that presently stand apart from each other because of their historical focus on specific organs and diseases.
Fundamental information about the basic mechanisms of aging still is woefully inadequate. Critically necessary is aging research in the basic disciplines of biology: genetics, biochemistry, cell biology, neurobiology, developmental biology, and others. The history of science amply demonstrates that major advances often come from serendipitous discoveries. Thus, in any agenda designed to establish priorities and to estimate the resources for aging research, it is of utmost importance that investigator-initiated research be protected. This should provide the core from which many major concepts and discoveries will emerge.
Research on basic cellular functions has brought many new insights into the biological mechanisms of aging (Röhme, 1981; Stanulis-Praeger, 1981) and research gives ample reason for optimism. Equally, new, improved, and expanded model systems for the study of aging have been uncovered; these include rodents from food-restricted colonies with enhanced lifespans and delayed, reduced, or absent age-related pathologies (Masoro, 1988); methods for the creation of strains of laboratory mice with a wide array of targeted mutations (selection of substrains with specific genetic characteristics); breeding lines of unusually long-lived insects from genetically heterogeneous stocks (Dice and Goff, 1987); and identification of a single gene mutation that increases lifespan in the nematode Caenorhabditis elegans. Progress has been made in the development of chemically defined media for cultivation of normal diploid somatic cells to facilitate analysis of mechanisms of clonal senescence and cellular repair.
Major conceptual and methodological advances in the techniques of molecular biology, especially in molecular genetics, are leading to an increased understanding of gene expression at the molecular level. Genetic maps are reaching high resolutions (markers at about one million nucleotide base pairs), with the potential for mapping and cloning the dominant genes responsible for such various age-