Abstract Domestic sheep were introduced in Mexico by the Spanish settlers in the 16th century. Nowadays, Mexico hosts several sheep breeds, adapting and evolving in both farming and traditional livestock production systems and different climate conditions. Research on the diversity of ovine genetic resources is urgently needed to prevent and reverse genetic erosion. Despite the relevance of Mexican sheep, data is still limited regarding their genetic diversity and history. We analysed the mitochondrial DNA (mtDNA) control region from different sheep breeds and municipalities of the State of Mexico, together with a large dataset of 542 sequences from America and the Iberian Peninsula. We identified a low genetic diversity in Mexican sheep, all belonging to haplogroup B. The phylogenetic analyses revealed low genetic distance among Cuba, Mexico, Portugal and Spain sheep populations, suggesting intense gene flow. Our results contribute for a better comprehension of the genetic diversity of domestic sheep in Mexico and Ibero-America.

中文翻译：

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墨西哥家羊的遗传多样性和系统地理学

摘要 16 世纪西班牙定居者将家养羊引入墨西哥。如今，墨西哥拥有多种绵羊品种，在农业和传统畜牧生产系统以及不同的气候条件下不断适应和进化。迫切需要研究绵羊遗传资源的多样性，以防止和扭转遗传侵蚀。尽管墨西哥绵羊具有相关性，但关于其遗传多样性和历史的数据仍然有限。我们分析了墨西哥州不同绵羊品种和城市的线粒体 DNA (mtDNA) 控制区域，以及来自美国和伊比利亚半岛的 542 个序列的大型数据集。我们在墨西哥绵羊中发现了低遗传多样性，都属于单倍群 B。系统发育分析显示古巴、墨西哥、葡萄牙和西班牙绵羊种群，表明强烈的基因流动。我们的结果有助于更好地理解墨西哥和伊比利亚美洲家养绵羊的遗传多样性。