Study of genetic diversity of wild Caspian trout Salmo trutta caspius in the Sardabrud and Astara Rivers, using D- Loop region sequencing

In this study the genetic diversity of wild Caspian trout (Salmo trutta caspius) in the Sardabroud and Astara Rivers was evaluated using D- Loop region sequencing. For this purpose, ۳۵ specimens of adult Caspian brown trout were collected from these rivers in the Mazandarn and Gilan Provinces in fall and winter ۲۰۱۱. Approximately ۳-۵ g of soft and fresh fin tissue was isolated and fixed in ethanol ۹۶% and then transferred to the Caspian Sea Ecology Research Center Genetics Laboratory in Sari, Iran. Genomic DNA from the samples was extracted using Ammonium Acetate Method. The quality and quantity of the extracted DNA were assessed by spectrophotometer and agarose gel (۱%) electrophoresis. Polymerase Chain Reaction (PCR) was performed on the target DNA using a primers sequence D- Loop region of mtDNA molecule. Then the product was purified and DNA sequencing was carried out using chain termination method. The D- Loop region of Caspian trout contained ۶۵۴ bp. Data were analyzed using Bio-Edit, DnaSP, Arlequin and Mega software. ۲۰ and ۱۵ haplotypes was observed in Sardabrud and Astara River. Tthe DNA sequence of one of them was recorded in Gene Bank with numbers KC۹۹۱۰۲۷ and KF۰۱۵۷۲۷. ۲۲۳ and ۲۴۰ polymorphic loci were detected in Sardabrud and Astara River that all of them were out of Hardy- Weinberg equilibrium (p<۰.۰۵). Average nucleotide and haplotype diversity were ۰.۱۲۷±۰.۰۶۷, ۱.۰۰۰±۰.۰۰۵ in Sardabrud River and ۰.۱۱۸±۰.۰۶۳ and ۱.۰۰۰±۰.۰۰۵ in Astara River.

Keywords:

Genetic diversity , Salmo trutta caspius , Sardabrud , Astara , Sequencing