Abstract
Genetic variability is crucial for enhancing economically important traits and for developing effective conservation strategies in livestock populations. In this study, genome-wide genetic variability and population divergence were evaluated in four native Turkish sheep breeds, known as Dağlıç (DGL), Sakız (SKZ), Pırlak (PRL), and Pırıt (PRT), using 366,544 single nucleotide polymorphisms (SNPs) generated by double-digest restriction-site associated DNA sequencing (ddRADseq). Across the four populations, the mean minor allele frequency (MAF) and nucleotide diversity (π) were estimated at 0.320 and 0.295, respectively. Observed heterozygosity (H(O)) ranged from 0.314 in the DGL breed to 0.323 in the SKZ breed. Expected heterozygosity (H(E)) values were consistently higher than the observed values across all breeds, with an overall mean of 0.327. The inbreeding coefficient (F(IS)) was negative in all populations, varying from - 0.034 in PRL to - 0.019 in DGL. Population structure analyses based on discriminant analysis of principal components (DAPC), ADMIXTURE, and TreeMix revealed a high level of admixture between the PRL and PRT populations, whereas the DGL breed was genetically distinct. In addition, TreeMix inferred a migration edge from the SKZ breed to the PRL-PRT clade. The high level of genetic variability observed in native Anatolian sheep breeds should be conserved to support diverse breeding strategies and to mitigate potential future challenges, particularly genetic bottlenecks. Further studies employing improved sampling strategies are recommended to obtain more robust insights into the genetic structure of native Anatolian sheep, especially for the PRL and PRT populations.