Is Longevity a Heritable Trait? Evidence for Non-genomic Influence from an Extended Longevity Phenotype of Drosophila melanogaster

摘要

Background: Although genetic variations are heritable, some quantitative traits like longevitymay have non-genomic influence on heritability. Laboratory-selected inbred strains of extendedlongevity phenotype of Drosophila offer an opportunity to study the inheritance of longevity.Objective: The aim of the study was to examine the heritability of longevity in an extended longevityphenotype of Drosophila melanogaster using reciprocal cross effects in F1 and F2 generations.Methods: Lifespan variations of virgin and mated flies in parent, F1 and F2 generations were investigatedusing reciprocal crosses between normal and long lifespan lines of inbred population of D.melanogaster. Heterosis, narrow-sense heritability, recombination loss, maternal effect and overdominancewith respect to survivorship in virgin and mated flies were analyzed.Results: Virgin flies lived longer than mated flies. There was no significant effect of mid-parentheterosis, recombination loss and overdominance on variations in longevity, whereas, significantmaternal effect and narrow-sense heritability were observed in mated and virgin flies, respectively.Conclusion: Absence of heterosis in our study population of Drosophila phenotypes could be dueto the lack of genetic heterogeneity. The heritability of the longevity trait in an inbred extendedlongevity phenotype depends on the variations in genetic and environmental factors.