Genetic structure of Caspian populations of stellate sturgeon, Acipenser stellatus (Pallas, 1771), using microsatellite markers

Abstract

Information about genetic relationships between populations of the stellate sturgeon <em>Acipenser stellatus</em> is scarce, despite its being commercially the most important and ecologically the most unique species in the Caspian Sea. We conducted a large-scale genetic analysis on diversity at the molecular level of stellate sturgeon populations at three sites (the estuaries of the Rivers Ural, Kura and Sefidrud) around the Caspian Sea, by tests on the genomic DNA with 15 sets of microsatellite markers (<em>LS-19, 34, 39, 54, 57, 62, 68, 69, Spl-105, 104, 163, 168, 170, 173, 113</em>). Ten primer sets were used to analyze the genetic variation in adults of the three populations. The analyses revealed that the average of alleles perlocus was 12.1 and all the sampled regions contained private alleles. The observed and expected heterozygosity averaged 0.674 and 0.860, respectively. The F_ST values ranged between 0.050 to 0.055, showing a significant difference between the three sites (<em>P</em> < 0.01). The genetic distance between populations was 0.530, thus indicating that the genetic difference among populations is pronounced. These results, combined with the highly significant R_ST of genotypic difference between pairs of collection sites, provide useful information on the genetic variation and differentiation among the Caspian Sea populations of the stellate sturgeon.