Distribution of multiple forms of lactate dehydrogenase, aspartate aminotransferase and serum esterase in herring from Norwegian waters

1. By use of combined starch and agar gel electrophoresis 10 samples (1258 specimens) were studied for serum esterase polymorphism, 13 samples (1454 specimens) for lactate dehydrogenase (LDH) polymorphism~ and one sample (100 specimens) for asparate aminotransferrase (AAT) polymorphism. The samples were collected in Norwegian waters and tlie North Sea. 2. In two groups of esterase (weak and strong components) ancl in LDH and AAT intraspecific, hereditable variations were observed. 3. Frequencies of LDH and AAT phenotypes were found to be similar to corresponding frequencies observed in samples from Canadian waters. 4. Statistically significant variations among samples were observed in distributions of tlie phenotypes, especially the esterase plienotypes