Quantitative Genetics of Postponed Aging in Drosophila melanogaster. I. Analysis of Outbred Populations

Abstract

Selection has been used to create replicated outbred stocks of Drosophila melanogaster with increased longevity, increased later fecundity, and increased levels of physiological performance at later ages. The present study analyzed the quantitative transmission patterns of such stocks, employing extensive replication in numbers of stocks, individuals, and assayed characters. The populations used derived from five lines with postponed aging and five control lines, all created in 1980 from the same founding base population. The following characters were studied: early 24-hr fecundity, early ovary weight, early female starvation resistance, early male starvation resistance, female longevity and male longevity. Numerous crosses were performed to test for non-Mendelian inheritance, average dominance, maternal effects, sex-linkage and between-line heterogeneity. There was only slight evidence for any of these phenomena arising reproducibly in the characters studied. These findings suggest the value of this set of stocks for studies of the physiological basis of postponed aging. GRICLIATTI 1984). This limitation on genetic analysis arises because Drosophila spp. are subject to inbreeding depression for fitness-related characters, like longevity (CLARKE and MAYNARD SMITH 1955), making the isolation of mutant strains with postponed aging very difficult.The use of selection is feasible for two reasons. First, there is abundant quantitative genetic variability for life-historical characters in outbred stocks of D. melanogaster (ROSE and CHARLESWORTH 198 la,b). Secondly, an indirect selection procedure can be used, in which natural selection is directed to act at later ages by the use of eggs laid by older females exclusively. When applied repeatedly over a number of generations, this type of selective screen leads to the evolution of postponed aging (WATTIAUX 1968a,b; ROSE and CHARLESWORTH 198 I b; ROSE 1984; LUCK- INBILL et al. 1984). This procedure also involves pop-'

SELECTION ON STRESS RESISTANCE INCREASES LONGEVITY IN DROSOPHILA MELANOGASTER

“…(Evidence for average additivity of starvation resistance alleles has been provided elsewhere [Hutchinson and Rose, 1991 ].) The average total increase in starvation resistance in the SB and SO lines is about 53 h, which was associated with an average total increase in longevity of about 14.5 days.…”

“…Ives (1970). Specifically, the experimental stocks started from a set of 10 populations derived from this Ives stock in February 1980, with five kept under an early reproduction (at 2 weeks of total age) regime (B) and five kept with later culture reproduction, at 10 weeks of total age, since 1981 (O) (Rose, 1984;Hutchinson and Rose, 1991). The "Os" have greater longevities than the "Bs."…”

“…Organisms with shortened lifespan could be dying because of novel pathologies unrelated to normal aging. For these reasons, it has been argued that the study of organisms undergoing postponed aging is likely to be the most successful approach (Hutchinson and Rose, 1987;Johnson, 1987;Rose, 1991, chap. 8).…”

“…This arises because of between-population, within-treatment variance, a variance component that such experiments systematically neglect. However, the solution to this problem is straightforward: multiple replication of selected and control populations from the outset of the experimental program (see Luckinbill et al, 1984;Rose, 1984;Service et al, 1985;Hutchinson and Rose, 1991 ).…”

Association of late childbearing with healthy longevity among the oldest-old in China

“…Hutchinson and Rose, 1991;Kirkwood and Rose 1991;Perls, 1997;Perls and Fretts, 2001;Perls, Kunkel, and Puca, 2002), our another hypothesis is that women who had 3+ births after age 35 or 2 or 3+ births after age 40 and who survived healthy up to the oldest-old ages 80-105 may have specific longevity gene(s) or other unobserved biological characteristics. Such genetic and/or biological characteristics may be associated with higher fecundity after ages 35-40 and healthy longevity among women.…”