Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK.
Anim Genet. 2013 Feb;44(1):53-61. doi: 10.1111/j.1365-2052.2012.02371.x. Epub 2012 May 21.
Many events in the history of eastern Eurasia, including the process of domestication itself, the initial spread of domestic horses and subsequent movements, are believed to have affected the genetic structure of domestic horse populations in this area. We investigated levels of within- and between-population genetic diversity in 'non-breed horses' (working horses sampled in remote areas) from 17 locations in Asia and parts of Eastern Europe, using 26 autosomal microsatellite loci. Non-breed horses have not been subject to the same intensity of artificial selection and closed breeding as have most breed animals and are thus expected to better reflect the population history of domestic horses. Despite geographic distances of between 300 and 7000 km between sampling locations, pairwise F (ST) was very low (range: <0.001 to -0.033), suggesting historically high levels of gene flow. Our analyses of non-breed horses revealed a pattern of isolation by distance and a significant decline in genetic diversity (expected heterozygosity and allelic richness) from east to west, consistent with a westward expansion of horses out of East Asia. Although the timing of this putative expansion is unclear, our results highlight the benefit of studying animals that do not belong to particular breeds when investigating aspects of a population's history.
许多发生在东亚地区的历史事件，包括驯化本身的过程、家马的最初传播以及随后的迁徙，都被认为影响了该地区家马种群的遗传结构。我们使用 26 个常染色体微卫星基因座，研究了来自亚洲 17 个地区和东欧部分地区的“非品种马”（在偏远地区采集的工作马）的种群内和种群间遗传多样性水平。非品种马没有像大多数品种动物那样受到同样强度的人工选择和封闭繁殖的影响，因此预计能够更好地反映家马的种群历史。尽管采样地点之间的地理距离在 300 到 7000 公里之间，但成对的 F（ST）非常低（范围：<0.001 到-0.033），表明历史上有高水平的基因流动。我们对非品种马的分析揭示了一种距离隔离的模式，以及遗传多样性（预期杂合度和等位基因丰富度）从东向西的显著下降，这与马从东亚向西扩张的模式一致。虽然这种扩张的时间尚不清楚，但我们的研究结果强调了在研究种群历史的某些方面时，研究不属于特定品种的动物的好处。
