We aimed to determine whether casein variants that are currently segregating in ovine populations existed before the domestication of sheep or, to the contrary, if their emergence is much more recent. To this end, we have retrieved whole-genome sequences from Iranian and domestic sheep from Africa, Europe, South and East Asia and West Asia. Population structure analysis based on 55,352,935 SNPs revealed a clear separation between Iranian mouflons and domestic sheep. Moreover, we also observed a strong genetic differentiation between Iranian mouflons sampled in geographic areas close to Tehran and Tabriz. Based on sequence data, hundreds of SNPs mapping to the casein αS1 (CSN1S1, 248 SNPs), casein αS2 (CSN1S2, 268 SNPs), casein ß (CSN2, 146 SNPs) and casein κ (CSN3, 112 SNPs) genes were identified. Approximately 25-63.02% of the casein variation was shared between Iranian mouflons and domestic sheep, and the four domestic sheep populations also shared 44.2-57.4% of the casein polymorphic sites. These findings suggest that an important fraction of the casein variation present in domestic sheep was already segregating in the mouflon prior to its domestication. Genomic studies performed in horses and dogs are consistent with this view, suggesting that much of the diversity that we currently detect in domestic animals comes from standing variation already segregating in their wild ancestors.

中文翻译：

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比较亚洲mouflon和家养绵羊中酪蛋白基因的多样性。

我们旨在确定在绵羊种群驯化之前是否存在目前在绵羊种群中分离的酪蛋白变体，或者相反，如果它们的出现是最近的话。为此，我们从非洲，欧洲，南亚，东亚和西亚的伊朗和家养绵羊中检索了全基因组序列。根据55,352,935个SNP进行的种群结构分析显示，伊朗的穆尔穆隆人和家养绵羊之间存在明显的分隔。此外，我们还观察到在靠近德黑兰和大不里士的地理区域采样的伊朗穆夫勒犬之间存在强烈的遗传分化。根据序列数据，鉴定了数百个SNPs，它们分别映射到酪蛋白αS1（CSN1S1，248 SNP），酪蛋白αS2（CSN1S2，268 SNP），酪蛋白β（CSN2，146 SNP）和酪蛋白κ（CSN3，112 SNPs）基因。大约25-63。伊朗穆福隆人和家养绵羊共有酪蛋白变异的02％，并且四个家养绵羊种群也拥有酪蛋白多态性位点的44.2-57.4％。这些发现表明，家养绵羊中存在的酪蛋白变异的重要部分已经在mouflon驯化之前被隔离。在马和狗中进行的基因组研究与这种观点是一致的，这表明我们目前在家畜中发现的许多多样性来自已经在其野生祖先中隔离的站立变异。这些发现表明，家养绵羊中存在的酪蛋白变异的重要部分已经在mouflon驯化之前被隔离。在马和狗中进行的基因组研究与这种观点是一致的，这表明我们目前在家畜中发现的许多多样性来自已经在其野生祖先中隔离的站立变异。这些发现表明，家养绵羊中存在的酪蛋白变异的重要部分已经在mouflon驯化之前被隔离。在马和狗中进行的基因组研究与这种观点是一致的，这表明我们目前在家畜中发现的许多多样性来自已经在其野生祖先中隔离的站立变异。