Polymorphism Evaluation of Various Genomic Loci in the Kıvırcık Sheep Breed of Turkey


Abstract: : In recent years regions which exhibit many genetic polymorphisms for the DNA of cattle, sheep and goats have been discovered. The aim of this study is to analyse the polymorphism of various microsatellites, which have been previously defined as polymorphism for sheep, and to evaluate the use of the Kıvırcık sheep population, which is indigenous to Turkey in relationship testing. The results have been evaluated for heterozygosity, power exclusion, matching probability, power discrimination, and paternity index. For DNA extraction, the chelex and phenol-chloroform-isoamyl alcohol methods were applied to the blood taken from animals. After measuring the amount and degree of purity of the DNA with a spectrophotometer, 7 DNA loci were amplified by PCR. The amplification products were stained with EtBr and examined with 1.5% agarose gel electrophoresis. Using denaturated polyacrylamide gel electrophoresis and silver staining, PCR products were evaluated and phenotypes of the alleles were determined. The OarFCB129 locus was observed to have a tendency to deviate from Hardy Weinberg Equilibrium in the general population (P = 0.0037; P < 0.05). The heterozygosity, power exclusion, power discrimination and matching probability were estimated for each locus. In 10 STR/microsatellite loci the highest heterozygosity value was 0.857 in the OarHH41 locus and the lowest value was 0.650 in the OarFCB266 locus in this study. The highest exclusion probability value was 0.71 in the OarHH41 locus and the lowest value was 0.36 in the OarFCB266 locus. The highest power discrimination value was 0.968 in the OarHH41 locus and the lowest value was 0.820 in the OarFCB266 locus. The OarFCB266, OarHH64 and OarHH51 loci have the highest values, and the OarHH41, OarFCB19 and OarFCB20 loci have the lowest values for matching probability. When all 10 loci were used together, the combined power discrimination and exclusion values were 0.0999706 and 0.999999, respectively. Among these loci, OarHH41, OarFCB19, OarFCB20, OarVH110, OarFCB128, OarFCB48 and OarFCB129 had high power discrimination and power exclusion and are recommended for use in determining relationships for their easy typing.

Keywords: Heterozygosity, genetic markers, exclusion probability, microsatellite, polymorphism, Kıvırcık.

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