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Atlantic salmon have been reared in the British Columbia, Canada aquaculture industry since the early 1980s. No breeding programmes spanned the entire production period and pedigree records were not kept for broodstocks prior to or since importation. Of the three recognized industry strains, two are of European ancestry (‘Mowi’ from Norway and‘McConnell’ from Scotland) and one is of North American heritage (‘Cascade’ from Gaspé, Quebec). We evaluated the amount and distribution of genetic variation within industry broodstocks by surveying microsatellite variation at 11 loci in 20 broodstock groups sampled from major production facilities. Allelic richness averaged 10.9 (range 5.8–13.8), compared with a value of 20.3 obtained for a North American wild population. Pairwise genetic distances (DS) between samples within strains were generally less than those between strains, with samples attributed to the same strain clustering together in a neighbour-joining dendrogram. Nevertheless, average distances between samples within the European strains were high (0.41 for Mowi; 0.71 for McConnell) but lower (0.06) for the Cascade strain. The reduced intra-sample and increased intra-strain genetic variation observed for the BC domesticated samples compared with wild populations was similar to observations for European domesticated Atlantic salmon. Evidence of introgression of the Cascade strain into European broodstocks was provided by the presence of largeSsa202alleles (confined to North America in wild populations) in some Mowi and McConnell samples. Introgression likely also contributed to the decreased intercontinental genetic distance for the domesticated samples of this study compared with that observed for wild populations. [ABSTRACT FROM AUTHOR]

The DNA sequences of four exons of the MHC (major histocompability complex) were examined in chinook salmon (Oncorhyynchus tshawytscha) from an interior (Nechako River) and a coastal (Harrison River) population in the Fraser River drainage of British Columbia. Mhc class I A1, A2 and A3 sequences and a class II B1 sequences were obtained by PCR from each of 16–20 salmon from each population. The calss I A1 and a pair of linked A2-A3 exons were derived from two different classical salmonid class I genes, Sasa-A and Onmy-UA, respectively. Allelic variation for B1, A1 and A2 was characterized by the high levels of nonsynonymous substitution indicative of the effects of natural selection on Mhc domains that contain peptide binding regions. The number of alleles detected at each of the four exons ranged from three (B1) to 22 (A1), but levels of nucleotide sequence divergence at all four exons were low relative to classical mammalian Mhc genes. The nucleotide similarly among alleles ranged between 89 and 99% over all exons, and all four domains possessed only two major sequence motifs. Allelic distributions at B1, A1 and A3 confirmed the genetic distinctiveness of the Harrison and Nechako chinook salmon populations revealed in previous studies. The two major allellic motifs of B1 and A1 segregated strongly between the populations. In spite of evidence that allelic diversity at these chinook salmon Mhc exons has been generated by selection, the level and distribution of diversity in the two salmon populations strongly reflected the demographic history of the species, which has been characterized by repeated bottlenecks and isolation-by-distance in glacial refugia. [ABSTRACT FROM AUTHOR]

Strongylocentrotus franciscanus is a keystone marine herbivore in the Pacific North West of North America, that is commercially harvested for its roe in wild fisheries and is under development as an aquaculture species. We report the development of 11 novel, highly polymorphic di- and trinucleotide loci for use in population studies of this species. In a survey of over 200 individuals from three coastal sites in British Columbia, observed heterozygosities of the loci ranged from 0.39 to 0.85 and an average of 26 alleles per locus were resolved. Seven of the 11 microsatellite loci were in Hardy–Weinburg equiulibruim (HWE). [ABSTRACT FROM AUTHOR]

Examines the characterization of microsatellite loci in Sebastes alutus and their conservation in congeneric rockfish species. Extraction of genomic DNA for a DNA library of S. alutus; Extraction of genomic DNA for microsatellite analysis; Size-fractionation of polymerase chain reaction products; Testing of microsatellite loci on congenerick rockfish species.

Studies tri- and tetranucleotide repeat microsatellite loci in Atlantic cod. Genomic DNA libraries; Number of alleles in a given locus.