High throughput methods for screening genetic variants that are phenotypically distinguishable are provided. Methods for identifying "long-lived" genetic variants among a set of variants are also provided. Methods for identifying pharmaceutical compounds that can promote longevity in various subjects, including mammals, and that can delay the onset of various diseases associated with aging are also provided. Various vectors and host cells containing identified genes/gene products are useful for screening longevity-promoting compounds that can interact with life-span-regulating genes/gene products. Pharmaceutical compositions that can promote longevity are also provided.