Genetic diversity and relationship among indigenous Turkish Karayaka sheep subpopulations

Abstract

The Karayaka is the most populous sheep breed in the Black Sea region of Turkey. In the present study, we investigated the intra- and inter-population genetic relationships among indigenous Karayaka sheep subpopulations. Nine microsatellites were genotyped for 64 individuals from Samsun, Ordu, Giresun and Tokat provinces. The average number of alleles (N-a), allelic richness (A(r)), observed heterozygosity (H-o), expected heterozygosity (H-e), polymorphism information content (PIC) and inbreeding coefficient (F-IS) for all subpopulations were estimated as N-a = 16.44, A(r) = 9.887, H-o = 0.303, H-e = 0.886, PIC = 0.866 and F-IS = 0.630, respectively. The observed and expected heterozygosity ranged from 0.171 (Giresun) to 0.376 (Ordu) and 0.757 (Samsun) to 0.845 (Ordu), respectively. It was determined that a 10.5 % of total genetic variation (F-IT = 66.9 %) in Karayaka sheep corresponded to genetic differences among subpopulations (F-ST), whereas 63.0 % was explained by genetic difference among individuals (F-IS). This study gives the first evidence about genetic relationships of Karayaka subpopulations. The results show that Karayaka sheep subpopulations are genetically different from each other. These findings revealed that the Karayaka breed has discrete subpopulations and should be taken into consideration when preparing conservation programs and future breeding strategies.