Microsatellite-Based Assessment of Genetic Variation and Demographic Bottlenecks in Kilis Goats Between Two Agro-Ecological Zones

Öz

The Kilis goats, one of Türkiye's prominent indigenous goat breeds, are extensively raised in the southern regions of the country due to its exceptional milk production potential. This study aimed to investigate the population dynamics of the Kilis goats, which are renowned for their high milk yield and remarkable adaptability, at the molecular genetic level. A total of 190 individuals from Kilis goat populations raised in two different provinces were characterized using 16 microsatellites. A total of 274 alleles were detected across all loci studied. The results for the mean number of alleles, expected heterozygosity, and polymorphic information content were 17.13, 0.85, and 0.83, respectively. It was revealed that 99.0% of the total genetic variation can be attributed to genetic differences among individuals, while only 1.0% can be explained by differences among populations. The FST value obtained (0.022) indicates a low level of genetic differentiation between the studied populations. These findings consistently indicate a high degree of genetic similarity and effective gene flow between the two provincial populations. STRUCTURE analysis revealed the presence of three distinct genetic clusters among the studied populations, indicating intra-breed sub structuring rather than clear inter-population divergence. Bottleneck analysis the analysis produced an L-shaped curve in the allele frequency distribution, indicating no significant recent genetic bottleneck in the studied populations. This study provides important insights into the genetic diversity and population structure of Kilis goat populations raised in the Gaziantep and Kilis provinces. The results demonstrate that the Kilis goat population exhibits high genetic diversity. Overall, the results highlight substantial within-breed genetic diversity, low inter-population differentiation, and the absence of a recent demographic bottleneck, providing a scientific foundation for sustainable genetic management.

Anahtar Kelimeler

• Kilis goats
• Fertile crescent
• Genetic diversity
• Small ruminant

İki Tarımsal-Ekolojik Bölgedeki Kilis Keçilerinde Mikrosatellit Belirteçlerle Genetik Çeşitlilik ve Demografik Darboğazların Değerlendirilmesi

Öz

Türkiye’nin önemli yerli keçi ırklarından biri olan Kilis keçisi, yüksek süt verim potansiyeli nedeniyle özellikle ülkenin güney bölgelerinde yaygın olarak yetiştiriciliği yapılmaktadır. Bu çalışmada, yüksek süt verimi ve dikkat çekici adaptasyon yeteneği ile bilinen Kilis keçilerinin popülasyon dinamiklerinin moleküler genetik düzeyde araştırılması amaçlanmıştır. Çalışmada, iki farklı ilde yetiştirilen Kilis keçisi popülasyonlarına ait toplam 190 birey, 16 mikrosatellit belirteç kullanılarak incelenmiştir. İncelenen tüm lokuslarda toplam 274 allel tespit edilmiştir. Ortalama allel sayısı, beklenen heterozigotluk ve polimorfik bilgi içeriği bakımından değerler sırasıyla 17.13, 0.85 ve 0.83 olarak tespit edilmiştir. Toplam genetik varyasyonun %99.0’ının bireyler arası genetik farklılıklardan kaynaklandığı, yalnızca %1.0’ının ise popülasyonlar arasındaki farklılıklarla açıklanabildiği ortaya konulmuştur. Elde edilen FST değeri (0.022), incelenen popülasyonlar arasında düşük düzeyde genetik farklılaşma olduğunu göstermektedir. Bu bulgular, iki ildeki popülasyonlar arasında yüksek düzeyde genetik benzerlik ve etkin gen akışı bulunduğunu tutarlı biçimde ortaya koymaktadır. STRUCTURE analizi, incelenen popülasyonlarda üç farklı genetik kümenin varlığını ortaya koymuş olup, bu durum belirgin popülasyonlar arası ayrışmadan ziyade ırk içi alt yapılanmaya işaret etmektedir. Bottleneck analizi sonucunda, allel frekans dağılımında L-şekilli bir eğri elde edilmiş ve bu durum, incelenen popülasyonlarda yakın geçmişte önemli bir genetik darboğaz yaşanmadığını göstermiştir. Bu çalışma, Gaziantep ve Kilis illerinde yetiştirilen Kilis keçisi popülasyonlarının genetik çeşitliliği ve popülasyon yapısı hakkında önemli bilgiler sunmaktadır. Elde edilen sonuçlar, Kilis keçisi popülasyonunun yüksek genetik çeşitlilik sergilediğini ortaya koymaktadır. Genel olarak bulgular, yüksek düzeyde ırk içi genetik çeşitlilik, düşük popülasyonlar arası farklılaşma ve yakın geçmişte demografik bir darboğazın bulunmadığını göstermekte olup, Kilis keçisinin sürdürülebilir ıslah stratejileri için bilimsel bir temel sağlamaktadır.

Anahtar Kelimeler

• Kilis keçisi
• Bereketli hilal
• Genetik çeşitlilik
• Küçükbaş hayvan

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