Mutagen-Mutation Equilibria in Evolution
Mutations do not entirely occur at random in the genome. This is evident for specific types of somatic mutations in mammals (Baltimore 1981; Golub 1987; Meyer et al. 1986) and for transposon-induction of mutations in the germ line (Engels and Preston 1984; O’Hare and Rubin 1983; Rubin et al. 1982; see also Campbell 1983, and Syvanen 1984).
Mutation rates are adjusted to evolutionary requirements. This has since long been discussed controversially (Benado et al. 1976; Biémont et al. 1987; Chao et al. 1983; Cox and Gibson 1974; Dobzhansky et al. 1952; Gillespie 1981; Holsinger and Feldman 1983; Ives 1950; Nöthel 1983, 1987; Sturtevant 1937) but seems more likely in view of the surprising mixture of error-proof and error-prone (i.e. mutagenic) mechanisms of DNA repair (Kimball 1987).
In diploids, the genetic load due to recessive variants is not a mutational load that has to be avoided in order to gain optimal population fitness, but mainly is a tolerable “segregational noise” produced by selectively favoured heterozygotes according to the “balance-hypothesis”.
KeywordsMutation Rate Genetic Load Immature Oocyte Hybrid Male Hybrid Dysgenesis
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- Biémont C (1986) Polymorphism of the mdg-1 and I mobile elements in Drosophila melanogaster.Chromosoma (Berl) 93: 393–397Google Scholar
- Bingham PM, Kidwell MG, Rubin GM (1982) The molecular basis of P-M hybrid dysgenesis: The role of the P element, a Pf-strain-specific transposon family. Cell 29: 995–1004Google Scholar
- Campbell A (1983) Transposons and their evolutionary significance. In: Nei M, Koehn RK (eds) Evolution of genes and proteins. Sinauer, Sunderland, pp 258–279Google Scholar
- Cox EC, Gibson TC (1974) Selection for high mutation rates in chemostats. Genetics 77: 169– 184Google Scholar
- Doerjer F, Bedell MA, Oesch F (1984) DNA adducts and their biological relevance. In: Obe G (ed) Mutations in man. Springer, Berlin Heidelberg New York TokyoGoogle Scholar
- Holsinger KE, Feldman MW (1983) Modifiers of mutation rate: Evolutionary optimum with complete selfing. Proc Natl Acad Sci USA 80: 6732–6734Google Scholar
- King RC (1970) Ovarian development in Drosophila melanogaster. Academic Press, LondonGoogle Scholar
- Lindsley DL, Grell EH (1968) Genetic variations of Drosophila melanogaster. Carnegie Inst Wash Publ No 627Google Scholar
- Mukai T (1979) Polygenic mutation. In: Thompson JN, Thoday JM (eds) Quantitative genetic variation, Academic Press, Lond, pp 177–196Google Scholar
- Nöthel H (1969) Genetische Konstitution und Strahlenempfindlichkeit. Habilitationsschrift, Freie Universität BerlinGoogle Scholar
- Sankaranarayanan K, Sobels FH (1976) Radiation genetics. In: Ashburner M, Novitski E (eds) The genetics and biology of Drosophila. Academic press, Lond, vol lc pp 1089–1250Google Scholar
- Vogel E, Natarajan AT (1979) The relation between reaction kinetics and mutagenic action of mono-functional alkylating agents in higher eukayotic systems. I. Recessive lethal mutations and translocations in Drosophila. Mutat Res 62: 51–100Google Scholar