Genetic diversity of Caspian brown trout (Salmo trutta caspius Kessler, 1877) in the Cheshmeh Kileh and Kargan Rud Rivers using microsatellite markers

Caspian brown trout (Salmo trutta caspius) is one of the nine subspecies of brown trout (Salmo trutta) in the world and is one of the economically important species and endangered in the Caspian Sea. In this study, the genetic diversity of the Caspian brown trout was investigated using microsatellite method. For this purpose, 225 specimens of adult Caspian brown trout were collected from Cheshmeh Killed and Kargan Rud rivers and genomic DNA was extracted using Ammonium Acetate method. The quality and quantity of the extracted DNA was assessed using a horizontal electrophoresis in 1% agarose gel and spectrophotometry methods. The Polymerase Chain Reaction (PCR) was performed using 16 pairs SSR primers and the amplified products were vertical electrophoresis using 6% polyacrylamide gel and were stained using silver nitrate method. DNA bands were scored using Photo- Capt software and produced five polymorphic loci. The mean observed and expected heterozygosity was calculated 0.47±0.09 and 0.61±0.10 respectively and more loci were out of Hardy- Weinberg equilibrium (P<0.001). Analysis of molecular variance (AMOVA) showed significant differences in genetic diversity between and within populations (P<0.01). So there is more than one population in studied rivers that should be considered in restructuring reserves.