Genetic variability of the short-haired and roughhaired Segugio Italiano dog breeds and their genetic distance from the other related Segugio breeds

The short-haired Segugio Italiano and rough-haired Segugio Italiano are two breeds of Italian scenthound. The two breeds were subjected to divergent selection based on the type (long versus short) and pigmentation (fawn versus black & tan) of the hair, leading to the development of the two above-mentioned phenotypes. Microsatellites markers from 120 unrelated dogs were used to estimate the genetic variability within the two Segugio Italiano breeds and to assess if divergent selection for the two phenotypes has possibly led to the development of subpopulations distinguished by coat type and pigmentation. Finally, we also estimated the genetic distance between the two Segugio Italiano breeds and two other related breeds, Segugio Maremmano and Segugio dell'Appennino. The mean Fis, Fit and Fst values indicated a moderate level of inbreeding. In both breeds the mean observed heterozygosity was lower than the expected heterozygosity. The AMOVA, PCoA and STRUCTURE analyses showed lack of differentiation between the two breeds and the absence of substructuring in the population. Cavalli- Sforza chord distance, Nei's genetic distance and Reynolds–Weir Cockerham’s genetic distance between the two Segugio Italiano breeds were low. Low genetic distances were also found between the Segugio Italiano and the others two related breeds indicating that there is no difference in terms of genetic distance among the three breeds despite the important phenotypic differences among them. This paper provides a basis to change the breeding guidelines of the four breeds in the light of these informations.