Mitochondrial DNA and allozyme analysis of Atlantic salmon, Salmo salar L., in England and Wales

Allozyme variation was examined in 429 Atlantic salmon, from seven sampling sites in England and Wales. Contingency tests for genetic homogeneity using three diagnostic loci revealed no significant differences among populations from the north-east and north-west of the U.K., but detected significant aspartate aminotransferase (AAT) differences between these samples and those from the R. Itchen in Hampshire (southern England). Mitochondrial DNA variation was analysed in 40 salmon from five spawning sites in the R. Itchen. Eight restriction endonucleases were used, of which three (AVAII, HAE III and HINFI) revealed polymorphisms. Six matriarchal lineages were discriminated. Two of the six mtDNA types observed were site-specific. These results suggest a reasonable expectation of discriminating spawning aggregations of Atlantic salmon.