Abstract
Allozyme variation in a population of the common mussel Mytilus edulis in Mumbles, South Wales, has been studied by starch gel electrophoresis. On the basis of data obtained for 34 loci, we estimate the proportion of loci polymorphic to be 30%. Using only the 29 loci for which individual genotypes can be accurately typed, the average heterozygosity is estimated to be 9.5±3.6%. The calculated expected average heterozygosity based on Hardy-Weinberg expectations is identical with the observed value. Allele frequency data at six polymorphic loci are given for several other British populations. There is no significant geographic heterogeneity. The results are discussed in relation to genetic adaptive strategies and are shown to be inconsistent with the predictions of the neutral hypothesis.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Ahmad, M., and Beardmore, J. A. (1976). Genetic evidence that the “Padstow Mussell” is Mytilus galloprovincialis. Mar. Biol. 35139.
Ayala, F. J., Powell, J. R., Tracey, M. L., Mourao, C. A., and Perez-Salas, S. (1972). Enzyme variability in the Drosophila willistoni group. IV. Genic variation in natural populations of Drosophila willistoni. Genetics 70113.
Ayala, F. J., Valentine, J. W., Hedgecock, D., and Barr, L. G. (1975). Deep-sea asteroids: High genetic variability in a stable environment. Evolution 29203.
Balagot, B. P. (1971). Microgeographic variation at two biochemical loci in the Blue Mussel, Mytilus edulis. M.A. thesis, State University of New York, Stony Brook.
Bayne, B. L. (1976). In Bayne, B. (ed.), Marine Mussels, Cambridge University Press, Cambridge.
Bayne, B. L., Widdows, J., and Thompson, R. J. (1976). Physiological integration. In Bayne, B. (ed.), Marine Mussels, Cambridge University Press, Cambridge.
Boyer, J. F. (1974). Clinal and size-dependent variation at the LAP locus in Mytilus edulis. Biol. Bull. (Woods Hole Mass.) 147535.
Ewens, W. (1972). The sampling theory of selectively neutral alleles. Theor. Popul. Biol. 387.
Hopkinson, D. A., Mestriner, M. A., Cortner, J., and Harris, H. (1973). Esterase D. A new human polymorphism. Ann. Hum. Genet. 37119.
Johnson, A. G., and Utter, F. M. (1973). Electrophoretic variations of aspartate aminotransferase of the bay mussel Mytilus edulis (Linnaeus, 1758). Comp. Biochem. Physiol. 44B317.
Johnson, A. G., and Utter, F. M. (1975). Population differences of aspartate aminotrans ferase and peptidase in the bay mussel Mytilus edulis. Anim. Blood Groups Biochem. Genet. 671.
Kimura, M., and Crow, J. F. (1964). The number of alleles that can be maintained in a finite population. Genetics 49725.
Kimura, M., and Ohta, T. (1971). Protein polymorphism as a phase of molecular evolution. Nature (London) 229467.
King, J. L., and Jukes, T. H. (1969). Non-Darwinian evolution: Random fixation for selectively neutral alleles. Science 164788.
Koehn, R. K. (1975). Migration and population structure in the pelagically dispersing marine invertebrate Mytilus edulis. In Proceedings of the Third International Conference on Isozymes.
Koehn, R. K., and Mitton, J. B. (1972). Population genetics of marine pelecypods. I. Ecological heterogeneity and evolutionary strategy at an enzyme locus. Am. Nat. 10647.
Koehn, R. K., Turano, F. J., and Mitton, J. B. (1973). Population genetics of marine pelecypods. II. Genetic differences in microhabitats of Modiolus demissus. Evolution 27100.
Koehn, R. K., Milkman, R., and Mitton, J. B. (1976). Population genetics of marine pelecypods. IV. Selection, migration and genetic differentiation in the blue mussel Mytilus edulis. Evolution 302.
Levins, R. (1968). Evolution in Changing Environments, Princeton University Press, Princeton, N.J.
Levinton, J. (1973). Genetic variation in a gradient of environmental variability: Marine bivalvia (Mollusca). Science 18075.
Lewis, W. H. P., and Harris, H. (1967). Human red cell peptidases. Nature (London) 215351.
Lewontin, R. C. (1974). The Genetic Basis of Evolutionary Change, Columbia University Press, New York.
Milkman, R., and Beaty, L. D. (1970). Large scale electrophoretic studies of allelic variation in Mytilus edulis. Biol. Bull.) 139430.
Mitton, J. B., Koehn, R. K., and Prout, T. (1973). Population genetics of marine pelecypods. III. Epistasis between functionally related isoenzymes of Mytilus edulis. Genetics 73487.
Murdock, E. A., Ferguson, A., and Seed, R. (1975). Geographical variation in leucine aminopeptidase in Mytilus edulis L. from the Irish coasts. J. exp. Mar. Biol. Ecol. 1933.
Nass, C. A. G. (1959). The x2 test for small expectations in contingency tables, with special reference to accidents and absenteeism. Biometrika 46365.
Ohta, T. (1974). Mutational pressure as the main cause of molecular evolution and polymorphism. Nature (London) 252351.
Ohta, T., and Kimura, M. (1973). A model of mutation appropriate to estimate the number of electrophoretically detectable alleles in a finite population. Genet. Res. 22201.
Powell, J. R. (1975). Protein variation in natural populations of animals. Evol. Biol. 879.
Selander, R. K., and Kaufman, D. W. (1973). Genic variability and strategies of adaptation in animals. Proc. Natl. Acad. Sci. 701875.
Shaw, C. R., and Prasad, R. (1970). Starch gel electrophoresis of enzymes—a compilation of recipes. Biochem. Genet. 4297.
Skibinski, D. O. F., Ahmad, M., and Beardmore, J. A. (1977). Genetic evidence for naturally occurring hybrids between Mytilus edulis and Mytilus galloprovincialis. Evolution. In press.
Tracey, M. L., Bellet, N. F., and Gravem, C. D. (1975). Excess allozyme homozygosity and breeding population structure in the mussel Mytilus californianus. Mar. Biol. 32303.
Valentine, J. W. (1976). Genetic strategies of adaptation. In Ayala, F. J. (ed.), Molecular Evolution, Sinauer Associates Sunderland, Mass.
Author information
Authors and Affiliations
Additional information
This work was supported in part by Grant No. GR3/2452 from the Natural Environment Research Council and Grant No. 101-74-7 ENV. U.K. from the EEC to J. A. Beardmore.
Rights and permissions
About this article
Cite this article
Ahmad, M., Skibinski, D.O.F. & Beardmore, J.A. An estimate of the amount of genetic variation in the common mussel Mytilus edulis . Biochem Genet 15, 833–846 (1977). https://doi.org/10.1007/BF00483980
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00483980