The biological archive
Abstract Increasing recognition of the importance of preserving genetic and other information of biological significance in potentially functional form over protracted periods of time has led many institutions to establish storage facilities in which living tissue, or its separated components, is maintained at temperatures below the freezing point of water, with or without accompanying changes of state. For at least two decades, the scientific and economic advantages of preserving bovine spermatozoa in the frozen state have been apparent, with the result that the practice of artificial insemination of dairy and beef cattle has assumed the proportions of a major industry. Essential to its technologically sound and financially profitable operations has been the creation of an infrastructure comprising carefully developed thermal processing protocols; the commercial availability of rugged refrigeration equipment suited to the demanding requirements of field distribution; effective inventory control methods and accessories; and, a variety of disposable products such as individual containers, protective media, cryogenic fluids and the like. The experience so obtained and its supporting technical base are now available for a large number of long term preservation missions many of which are of profound scientific importance, some involing materials that represent major investments in time and money in their original isolation and characterization, as well as anticipated expense associated with their indefinitely prolonged preservation and subsequent recovery and use. The implications of such operations are of great potential importance, not only to the scientific community and industrial groups, but to society at large. Critical evaluation of their methodologies, quality control procedures, performance standards, and results is essential.