AgroParisTech, Unité Mixte de Recherche 1313 Génétique Animale et Biologie Intégrative, Paris, France.
PLoS One. 2013 Apr 22;8(4):e61544. doi: 10.1371/journal.pone.0061544. Print 2013.
Since horse breeds constitute populations submitted to variable and multiple outcrossing events, we analyzed the genetic structure and gene flows considering horses raised in France. We used genealogical data, with a reference population of 547,620 horses born in France between 2002 and 2011, grouped according to 55 breed origins. On average, individuals had 6.3 equivalent generations known. Considering different population levels, fixation index decreased from an overall species FIT of 1.37%, to an average [Formula: see text] of -0.07% when considering the 55 origins, showing that most horse breeds constitute populations without genetic structure. We illustrate the complexity of gene flows existing among horse breeds, a few populations being closed to foreign influence, most, however, being submitted to various levels of introgression. In particular, Thoroughbred and Arab breeds are largely used as introgression sources, since those two populations explain together 26% of founder origins within the overall horse population. When compared with molecular data, breeds with a small level of coancestry also showed low genetic distance; the gene pool of the breeds was probably impacted by their reproducer exchanges.
由于马种构成了经历多种不同杂交事件的群体，我们分析了遗传结构和基因流动，考虑了在法国饲养的马。我们使用了系谱数据，参考群体是 2002 年至 2011 年间在法国出生的 547620 匹马，根据 55 个品种起源进行分组。平均而言，个体有 6.3 个已知的等效世代。考虑到不同的群体水平，固定指数从总体物种 FIT 的 1.37%下降到考虑 55 个起源时的平均 [公式：见正文] -0.07%，表明大多数马种构成了没有遗传结构的群体。我们说明了马种之间存在的基因流动的复杂性，一些种群对外来影响封闭，但大多数种群受到不同程度的渗入。特别是，纯血马和阿拉伯马品种被广泛用作渗入来源，因为这两个种群共同解释了整个马种群中 26%的起源。与分子数据相比，亲缘关系水平较低的品种也表现出较低的遗传距离；品种的基因库可能受到其繁殖者交流的影响。
