Preliminary studies on the genetic variability of six Hungarian common carp strains using microsatellite DNA markers

Genetic variation in six Hungarian common carp (Cyprinus carpio L.) strains was evaluated using 12 microsatellite loci. The domesticated (‘Tatai’, ‘Biharugrai’ and ‘Szarvasi’) strains were derived from fish farms. Two of wild strains (‘Tiszai’ and ‘Dunai’) were sampled from brood stocks maintained at fish farms for breeding, and ‘Kis-Balatoni’ wild carp were sampled from the Small Balaton Lake. Pairwise Fst-values (0.013–0.161) were highly significant (p < 0.0001), demonstrating differentiation among strains. The mean number of alleles ranged between 3.9 and 8.2. Overall mean observed heterozygosity was lower (0.557) than the mean expected heterozygosity (0.700). By strain, the only exception to this trend was the Dunai (Danubian), which showed higher mean observed heterozygosity (0.764) than expected (0.602). For five loci the Dunai strain showed extremely high levels of heterozygosity (1.00). Two wild strains exhibited a number of loci (Tiszai, 4; Dunai, 6) that were not in Hardy–Weinberg equilibrium. A relatively high number of private alleles overall (n=26), as well as differences in allele frequencies supported our ability to assign most individual fish (over 90%) to each strain.