Genetic differentiation of Pacific smelt Osmerus mordax dentex inferred from the data of mitochondrial DNA analysis

The population genetic structure of Pacific smelt Osmerus mordax dentex from 25 locations in the Sea of Japan, Okhotsk Sea, Bering Sea, Kara Sea, Barents Sea, and White Sea was examined based on mitochondrial DNA variability. The genetic structuring of O. m. dentex over the larger part of the examined Eurasian range was weakly expressed, despite the high level of haplotype diversity (0.770 +/- 0.154). Hierarchical analysis of molecular variance (AMOVA) showed that the majority of molecular diversity (89%) was found within the populations. The most considerable differentiation of geographical populations for those grouped by their association with sea basins was observed for the Sea of Japan, with mean I broken vertical bar ST values of 0.114 (based on data from restriction fragment length polymorphism (RFLP) analysis) and 0.115 (based on sequencing data) (p < 0.01).