Population genetic structure of Persian sturgeon (Acipenser persicus) between South Caspian Sea and Sefidrud River using DNA sequencing method

Abstract

The goal of this study was to analyse the population genetic structure of the Persian sturgeon (Acipenser persicus) between South Caspian Sea and Sefidrud River with mtDNA control region (Dloop gene) and DNA sequencing method during 2010 – 2012 sturgeon stock assessment project. Fish speciemns were collected by bottom trawl net. Extraction of DNA, PCR and DNA sequencing were carried out. Diversity index, the gamma distribution shape parameter for the rate heterogeneity among sites and nucleotide sequence, Fst index, exact test, the historical demographic pattern using neutrality tests and mismatch distribution analysis (D test of Tajima and Fs test of Fu) were analysed. Thirteen haplotypes were obtained, average (±SD) for haplotype diversity was 0.961 ± 0.101, nucleotide diversity was 0.038 ± 0.015, the gamma distribution shape parameter was 0.19, Fst index revealed little genetic structure between populations and the significant Fst value was seen by 10000 permutation only between Sefidrud River and Other Areas (P≤ 0.05) and was confirmed by exact test of population differentiation. Mismatch distribution for Acipenser persicus appeared to be unimodal, which closely matched the expected distributions under the sudden expansion model and supported by the low Harpending’s Raggedness index (0.061). Tajima’s D and Fu’s Fs statistics were -0.84 and - 0.220, respectively, and was not significant. The results of this study showed that the population of Acipenser persicus in Sefidrud River were genetically differentiated from South Caspian Sea and three other areas represented a single panmictic populations. Therefore, fisheries managements of this valuable species should be directed towards conservation of gene pools and increasing different populations.