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The goal for using genetic information derived from embryo samples is to gain insight into the reproductive biology of adult white sturgeon, Acipenser transmontanus Richardson. The relationship between egg development stages on the extraction of quality DNA was determined, and subsequent genotype data were used to infer contributing spawner numbers. White sturgeon DNA was present in extractions from all stages; however, pre-gastrulation stage embryos generally failed to amplify sufficient genetic loci for analysis. Using experimentally created families, multivariate ANOVA and maximum-likelihood sibship methods estimated the presence of 10 contributing parents from 11 actual adult spawners. It was observed that unidentified half-sibling relationships (offspring sharing one parent) caused error for inferring parent numbers. Genetic methods estimated 13–40 parents potentially contributed to a collection of wild-caught embryos, with variable numbers of parents inferred from separate spawning events (varying from 8 to 24). Egg source material provides a means to enhance the accuracy of annual spawning population size estimates, which is important for informing habitat restoration, harvest and water management decisions and recovery planning.

Recent advances in molecular interrogation techniques now allow unprecedented genomic inference about the role of adaptive genetic divergence in wild populations. We used high-throughput genotyping to screen a genome-wide panel of 276 single nucleotide polymorphisms (SNPs) for the economically and culturally important salmonid Oncorhynchus mykiss. Samples included 805 individuals from 11 anadromous and resident populations from the northwestern United States and British Columbia, and represented two major lineages including paired populations of each life history within single drainages of each lineage. Overall patterns of variation affirmed clear distinctions between lineages and in most instances, isolation by distance within them. Evidence for divergent selection at eight candidate loci included significant landscape correlations, particularly with temperature. High diversity of two nonsynonymous mutations within the peptide-binding region of the major histocompatibility complex (MHC) class II (DAB) gene provided signatures of balancing selection. Weak signals for potential selection between sympatric resident and anadromous populations were revealed from genome scans and allele frequency comparisons. Our results suggest an important adaptive role for immune-related functions and present a large genomic resource for future studies

An international multi-laboratory project was conducted to develop a standardized DNA database for Chinook salmon (Oncorhynchus tshawytscha ). This project was in response to the needs of the Chinook Technical Committee of the Pacific Salmon Commission to identify stock composition of Chinook salmon caught in fisheries during their oceanic migrations. Nine genetics laboratories identified 13 microsatellite loci that could be reproducibly assayed in each of the laboratories. To test that the loci were reproducible among laboratories, blind tests were conducted to verify scoring consistency for the nearly 500 total alleles. Once standardized, a dataset of over 16,000 Chinook salmon representing 110 putative populations was constructed ranging throughout the area of interest of the Pacific Salmon Commission from Southeast Alaska to the Sacramento River in California. The dataset differentiates the major known genetic lineages of Chinook salmon and provides a tool for genetic stock identification of ...

We describe the isolation, PCR amplification, and characterization of 10 new microsatellite loci (Ots-1–Ots-10) for the federally protected chinook salmon (Oncorhynchus tschawytscha). We investigate the inheritance and linkage of these loci as well as a previously published locus, Onem13, in families obtained from artificial crosses. Mendelian transmission is confirmed for 76 of 80 segregations observed. Of the four deviations, two appear to have resulted from gametic segregation distortion. The other two provide evidence for the existence of at least one null allele. We also identify ‘‘drop out’’ of large alleles in these two families owing to competitive PCR amplification of smaller alleles. There is no evidence for linkage between any pair of loci. One mutation observed at Ots-2 is reported and confirmed by DNA sequencing. We estimate the mutation rate at this locus to be 6.5 3 10–4 (95% confidence interval 3.6 3 10–3 to 1.6 3 10–4, respectively). Characterizing a mutant allele at Ots-2 offers the first step toward understanding mutation rates for chinook microsatellites. Owing to their Mendelian inheritance, these new loci provide reliable markers for high-resolution population genetics studies of this species.