Microsatellite variations and genetic structure of common carp (Cyprinus carpio) populations in Gomishan bay and Gorganroud River (Southeast of the Caspian Sea)

Common carp (Cyprinus carpio) population has been declined in the Caspian Sea in the recent years, mainly due to human manipulation. This valuable species needs to be protected in the Caspian Sea. Considering the commercial value of common carp, its rehabilitation program has been established. In the present study, 8 microsatellite loci were used to assess genetic variation and population structure of common carp in Gomishan bay (GB) and Gorganroud River (GR). These two regions are the most important habitat of common carp. Mean actual (Na) and expected (Ne) alleles numbers were 15.12 and 11.35 for GB and GR, respectively. Mean observed (Ho) and expected (He) heterozygocity were 0.99 and 0.90 for GB and GR, respectively. Results, also, showed that all investigated loci were polymorphic. Twelve out of 16 tested locus×region combinations showed significant deviation from Hardy-Weinberg equilibrium (HWE) which could be mainly due to increase in He. FST index was found to be 0.011. Hence, AMOVA showed that observed variation was related to within population (99%) as well as between populations (1%). According to the results, it is suggested that studied populations have a great allelic richness and gene flow.