The variation in non-specific esterases in the white muscles of two species of Galaxias in Tasmania

Abstract

The zymograms of non-specific esterases in white skeletal muscle of Galaxias auratus and G. truttaceus are given. The electrophoretic patterns of the two species are very similar. A total of 16 bands in G. auratus and 17 in G. truttaceus was identified. Of these, 14 were common to both species. It is suggested that 14 esterase loci operate in the white muscle of both species. The loci Est 14 and Est 8 in G. auratus and Est 1, Est 4 and Est 7 in G. truttaceus appear polymorphic. Each polymorphic locus possesses two co-dominant alleles, one which codes for an electrophoretically slow isozyme, and the other for a faster migrating enzyme. The Est 8 locus of G. auratus and the Est 1 locus of G. truttaceus which code for dark staining, and therefore easily scored isozymes, appear suitable for application to population genetics studies. Investigation of a single population of each species indicates that the alleles of both of the latter are in Hardy-Weinberg equilibrium.