Parental age dependent changes as a source of genetic variation in Drosophila melanogaster

Abstract

It has been shown repeatedly that numerous cumulative changes occur in chromosomes of D. melanogaster, as an effect of ageing which, especially in the homozygous state, significantly affect different fitness components of their carriers. It appears that the observed age-affected events are produced by systematic and ontogenetically programmed changes in genetic loads at specific chromosomes, which are transferable to following generations. It has been suggested that such changes could be of mutational origin, and that they could be more frequent at gene loci which are epigenetically active during ontogenesis. It was demonstrated that a large sample of identical chromosomes behave quite differently in the homozygous state when obtained from aged compared to non-aged parents, producing a significant decrease in relative viability, length of preadult development, and longevity of their carriers, as well as in the frequency of recombinations of corresponding chromosomes. A specific treatment by streptomycin resulted in remarkably milder effects of ageing, which is in accordance with the statement of some authors that such a treatment may diminish the frequency of spontaneous recessive mutations in their carriers. Thus the observed age-affected changes could be an important source of developmental and evolutionary variation of living organisms.

The song of the old mother: Reproductive senescence in female drosophila

“…60,81 One study failed to detect a difference in offspring viability between old parents (males and females >25 d pe) and young parents (>5 d pe), although the offspring of old parents developed significantly (16.4%) more rapidly than young parents. 82 Fertility is studied more precisely by observing the effects of female age on offspring viability at different life history stages including embryonic, larval, pupal, and adult. The degree to which maternal age affects these life stages varies.…”

Lamarckism and Ageing

“…Heritable changes in germ-line chroma tin, which are induced by physiological changes in the parent, could explain some intriguing results obtained by Marinkovid and Bajraktari [50], They found that when Drosophila melanogasler heterozygous for identical second chromosomes were crossed, the relative viability, length of preadult development and longevity of the homozygous progeny from 5-day-old par ents were lower than those of progeny from 25-day-old parents. Furthermore, the effect was cumulative: parental ageing during the previous three generations enhanced the differences.…”

Effects of pollutants from power plants in Kosova on genetic loads ofDrosophila melanogaster

“…Since the investigation of single pollutants is often not sufficient to draw conclusions for the presence of genetic hazards in the environment, we addressed this problem by the analysis of the genetic load of a population, meaning all mutations that affect the fitness of their carriers, and are characteristic for plant and animal populations in a particular environment (Muller, 1950). Since these macro-mutations, and especially micromutations, are mainly recessive, homozygotization is necessary to enable the detection and estimation of mutation loads in parts of the genome of a given species, that is, the X chromosome (Eanes et al, 1985) or chromosome II in D. melanogaster (Bajraktari et al, 1987a(Bajraktari et al, , 1987b(Bajraktari et al, , 1988Ives, 1945;Marinkovic and Bajraktari, 1988;Marinkovic and Krunic, 1967;Marinkovic et al, 1975;Stamenkovic-Radak et al, 1986). This approach is applied in population genetic studies (Marinkovic and Krunic, 1967;Stamenkovic-Radak et al, 1986), genetics of ageing (Marinkovic and Bajraktari, 1988;Marinkovic et al, 1973) and also in genotoxicity investigations (Bajraktari et al, 1987a(Bajraktari et al, , 1987b(Bajraktari et al, , 1988Marinkovic et al, 1975).…”

“…Since these macro-mutations, and especially micromutations, are mainly recessive, homozygotization is necessary to enable the detection and estimation of mutation loads in parts of the genome of a given species, that is, the X chromosome (Eanes et al, 1985) or chromosome II in D. melanogaster (Bajraktari et al, 1987a(Bajraktari et al, , 1987b(Bajraktari et al, , 1988Ives, 1945;Marinkovic and Bajraktari, 1988;Marinkovic and Krunic, 1967;Marinkovic et al, 1975;Stamenkovic-Radak et al, 1986). This approach is applied in population genetic studies (Marinkovic and Krunic, 1967;Stamenkovic-Radak et al, 1986), genetics of ageing (Marinkovic and Bajraktari, 1988;Marinkovic et al, 1973) and also in genotoxicity investigations (Bajraktari et al, 1987a(Bajraktari et al, , 1987b(Bajraktari et al, , 1988Marinkovic et al, 1975). The Drosophila test system is recently used as a comfortable and reliable approach for the investigation of genotoxic effects (Gürbüzel et al, 2013;Karadeniz et al, 2011).…”