Phylogenetic insights into three turkish native sheep breeds through microsatellite analysis

Abstract

Animal genetic resources are recognized as an indispensable component of humanity's natural heritage and are essential for ensuring environmental sustainability for future generations. The aim of this study was to investigate the genetic diversity, population structure, and presence of genetic bottlenecks in three indigenous Turkish sheep breeds: Dagl & imath;& ccedil;, Karagul, and Sak & imath;z, all of which are conserved as genetic resources in Turkiye. Genomic DNA was extracted from 140 blood samples using the salt precipitation technique. These samples were collected from the Sak & imath;z (n = 53), Dagl & imath;& ccedil; (n = 58), and Karagul (n = 29) breeds, which were reared on 13 farms located in the provinces of & Idot;zmir, Afyon, and Tokat. Genotyping of the DNA samples was performed using 17 microsatellite markers, resulting in the identification of 345 different alleles. The highest number of alleles observed for a single locus was 28, while the average effective allele number and polymorphic information content were 18.32 and 0.94, respectively. The calculated GST value indicated that a substantial 98.70% of the observed genetic variance resided within individuals. Breed-specific FIS values were determined as 0.132 for Sak & imath;z, 0.120 for Dagl & imath;& ccedil;, and 0.089 for Karagul. Analysis using STRUCTURE identified three ancestral populations contributing to the genetic composition of the sampled animals, with evidence of admixture across all populations. Utilizing three distinct mutation models within the Bottleneck program, bottleneck analysis revealed that the Sak & imath;z and Dagl & imath;& ccedil; breeds have largely maintained their recent effective population size, as supported by Wilcoxon tests and mode-shift plots. However, the Karagul breed exhibited evidence suggestive of a recent bottleneck (p < 0.05). Despite this indication, the overall genetic diversity within the studied breeds appeared to be relatively well-preserved. Given the limited size of the Karagul population, careful management of breeding strategies is essential to safeguard its existing genetic pool.