Microsatellite Polymorphism Reveals Low Genetic Differentiation between Fall and Spring Migratory Forms of Endangered Caspian Trout, Salmo trutta caspius (Kessler, ۱۸۷۰)

The main objective of this study was to assess genetic comparison of two migratory forms of Caspian trout Salmo trutta caspius namely fall-run and spring-run. Owing to the lack of information on its genetic differences, ۵ microsatellite loci were used for ۵۸ sample analyses. Genomic DNA was extracted from caudal fin using Roche DNA extraction kit and each PCR reaction was performed in a ۲۵ ?l reaction volume. Results revealed that the most allelic frequencies were observed in fall-runs of Caspian trout. The average observed and expected heterozygosity in fall-runs and spring-runs were ۰.۷۷۱۹, ۰.۶۱۰۸ and ۰.۴۴۳۵, ۰.۵۹۱۱, respectively. In both groups except Str۵۴۳INRA in spring runs, all loci had deviation from Hardy-Weinberg equilibrium. Furthermore except Str۵۴۳INRA in spring runs, expected heterozygosity in all loci was more than observed heterozygosity. In conclusion microsatellite loci polymorphism in this study reveals low genetic differentiation between fall-runs and spring-runs. 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کلیدواژه ها:

Salmo trutta caspius ، fall ، run ، spring ، genetic differentiation ، Microsatellite ، Caspian Sea