Genetics of Multiple Malate Dehydrogenase Isozymes in Skeletal Muscle of Walleye (Stizostedion vitreum vitreum)

Abstract

Electrophoresis of extracts of white skeletal muscle revealed a total of six phenotypes of malate dehydrogenase (MDH) (L-malate; NAD oxidoreductase, EC 1.1.1.37) isozymes in walleye (Stizostedion vitreum vitreum). The individual MDH phenotypes consisted of four or more MDH isozymes.The heritability of all six phenotypes was tested in a breeding experiment. The results of the breeding experiment provided evidence for the existence of three nondominant alleles at one MDH locus. Subcellular fractionations indicated that these three alleles code for a supernatant (extramitochondrial) form of MDH. The frequencies of these alleles varied in fish from four locations in western Canada.