Tinca Gobba Dorata del Pianalto di Poirino: genetic characterization by microsatellite markers

Poirino (Golden humped tench of Poirino highland, [PO]), the only Italian fish with the Protected Designation of Origin, was characterized by seven microsatellites and compared to three wild populations living in Italian lakes (Valagola [VA]; Trasimeno [TR]; Bolsena [BO]). The PO population showed high variability values (number of effective alleles: 2.70 vs. 1.62 to 2.20; expected heterozygosity: 0.49 vs. 0.29 to 0.40). The analysis of between-population differentiation indicated that PO significantly differed from the others (FST = 0.039 to 0.097, P<0.05), while BO and TR were the most similar, consistently with their geographic proximity. The Neighbour-Joining tree revealed a clear separation between Northern and Central populations, with a bootstrap support of 97%. The population differentiation was reflected by the results of the assignment test, with 64% to 92% of the individuals correctly assigned to the original population, and a probability ranging from 76% to 95%. No individuals belonging to other populations were erroneously assigned to PO. A more detailed analysis of the PO population showed a similar genetic variability within the 15 considered ponds and a low degree of differentiation between ponds, with the exception of ne “historical” pond, which significantly differed from most of the others, thus deserving to be preserved. The results indicate that the PO, despite being farmed, has a high level of withinpopulation diversity and is greatly differentiated from the other populations considered. The possibility of applying the assignment test in the framework of the product traceability deserves further investigation.