Determining Continent of Origin of Chum Salmon (Oncorhynchus keta) Using Genetic Stock Identification Techniques: Status of Allozyme Baseline in Asia

Abstract

A three-agency program was initiated in 1989 to develop a new multilocus genetic baseline for chum salmon (Oncorhynchus keta) in Japan and Russia for use in stock identification; allele frequencies at 77 allozyme loci are reported in 38 samples covering most of its north–south limits of distribution in Asia. In a 62-locus data set for 17 Japanese and 12 Russian samples, average heterozygosity ranged from 0.066 to 0.087 (mean 0.079) and the average number of P0.95 and P0.99 loci was 14 and 26, respectively. Tests of year-to-year variation in allele frequencies were not significant at five of six locations. For the P0.95 loci, FST values ranged from 0.007 (sMDH-B1*) to 0.154 (mAAT-2*) and averaged 0.038. A clear distinction between Russian and Japanese samples was observed at Nei's D = 0.006, and genetic differentiation generally followed a regional pattern within each country. Principal component analysis of the P0.95 loci revealed a large difference between Japanese and Russian samples. Four loci (sAAT-1,2*, mAAT-2*, LDH-A1*, and PEPLT*) had high loadings on the first two principal components. Analyses of a simulated fishery with 200 fish revealed a high degree of precision in estimating contributions to seven population groups and to country of origin.

Population structure and stock identification of chum salmonOncorhynchus ketafrom Japan determined by microsatellite DNA variation

“…Effective stock identification techniques rely on characteristics that display stable differentiation among groups to be discriminated, with the characters easily surveyed in a rapid and cost‐effective manner. Allozymes provided the characteristics for initial genetically based population surveys 7 and stock identification of Japanese chum salmon 8,40 . Later, DNA‐level variation in single nucleotide polymorphisms (SNPs) provided the characters by which population structure could be determined 11 and estimation of stock composition in mixed‐stock samples can proceed 41…”

“…Tissue samples have been collected from mature chum salmon at a number of rivers in Japan during previous analyses of genetic variation 8,10,11 . Additional tissue samples or extracted DNA were sent to the Molecular Genetics Laboratory at the Pacific Biological Station in Nanaimo, BC, Canada.…”

The genetic population structure of lacustrine sockeye salmon, Oncorhynchus nerka, in Japan as the endangered species

“…The genetic population structure of the Pacific salmon has been clarified using various methods such as allozyme (Winans et al 1994), mitochondrial DNA (mtDNA; Seeb and Crane 1999), and microsatellite DNA (msDNA; Beacham et al 2006). The mtDNA and msDNA methods are powerful tools for genealogical identification, despite limitations of analytical precision (Zhang and Hewitt 2003).…”

A Coordinated Research Plan for Estuarine and Ocean Research on Pacific Salmon

“…Some areas of early marine distribution (e.g., northern California, Alaska Peninsula, and Bering Sea) have been poorly sampled, and we have little information on the water masses occupied by salmon or seasonal salmon movement patterns. Continued analysis of coded-wire tagging data and increased use of genetic markers (Winans et al 1994(Winans et al , 1998 and archival tags (Boehlert 1997) will fill gaps in our knowledge of the oceanic distributions of most salmon stocks. 25, No.…”