MtDNA and microsatellite variation in Baltic Atlantic salmon

Variation in mtDNA and DNA microsatellites was examined in Atlantic salmon (Salmo salar) from three rivers that drain into the Baltic Sea in order to evaluate the usefulness of DNA markers for genetic characterization of Baltic salmon populations. Three microsatellite loci and variation in the mitochondrial ND1 gene were studied. Polymorphisms were found for all genetic markers studied. Three different haplotypes were found after restriction enzyme digestion of the ND1 gene. The distribution of these haplotypes varied significantly among the salmon populations. The microsatellites included one highly polymorphic locus with eight alleles, one with an intermediate level of variation and one locus with little variation. Two of the microsatellites showed significant differentiation among populations. The study demonstrates that mtDNA and microsatellites provide a large amount of variation useful in genetic studies of Baltic salmon. (C) 1997 International Council for the Exploration of the Sea.