Marker-based assessment of intra-flock relatedness and signals of recent demographic bottleneck in Andi sheep using a 12-Locus STR panel
https://doi.org/10.26897/2949-4710-2026-4-1-3-02
Abstract
The study presents a marker-based assessment of intra-flock relatedness and diagnostics of recent demographic bottleneck signs in Andi sheep using data from a 12-locus STR panel. The research material consisted of 40 Andi ewes genotyped across 12 autosomal STR loci. The mean panel-wide FIS was 0.026. For 780 unique pairwise comparisons the mean r value was 0.305, the median value was 0.292, the proportion of pairs with r ≥ 0.25 reached 78.8%, and 58 pairs fell within the range of 0.45-0.55. The aggregated allele-frequency distribution showed an L-shaped profile without mode shift. The mean M-ratio was 0.730, with a median of 0.733, which does not support the hypothesis of a recent severe demographic bottleneck. The results indicate significant intra-flock relatedness in the absence of recent sharp demographic bottleneck signs. The main genetic risks for the studied flock are likely associated not with recent demographic collapse but with family structure and limited use of breeding rams. The practical significance of the study lies in substantiating the need for regular marker-based monitoring of relatedness when preserving and breeding Andi sheep.
About the Author
Alimsoltan A. Ozdemirov
Federal Agrarian Scientific Center of the Republic of Dagestan
Russian Federation
Russian Federation
Alimsoltan A. Ozdemirov, CSc (Bio), Head of the Laboratory of Genomic Research, Selection and Breeding
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Review
For citations:
Ozdemirov A.A. Marker-based assessment of intra-flock relatedness and signals of recent demographic bottleneck in Andi sheep using a 12-Locus STR panel. Timiryazev Biological Journal. 2026;4(1):302. (In Russ.) https://doi.org/10.26897/2949-4710-2026-4-1-3-02
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