Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland;
Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.
Proc Natl Acad Sci U S A. 2021 Jun 22;118(25). doi: 10.1073/pnas.2100901118.
The Aceramic Neolithic (∼9600 to 7000 cal BC) period in the Zagros Mountains, western Iran, provides some of the earliest archaeological evidence of goat () management and husbandry by circa 8200 cal BC, with detectable morphological change appearing ∼1,000 y later. To examine the genomic imprint of initial management and its implications for the goat domestication process, we analyzed 14 novel nuclear genomes (mean coverage 1.13X) and 32 mitochondrial (mtDNA) genomes (mean coverage 143X) from two such sites, Ganj Dareh and Tepe Abdul Hosein. These genomes show two distinct clusters: those with domestic affinity and a minority group with stronger wild affinity, indicating that managed goats were genetically distinct from wild goats at this early horizon. This genetic duality, the presence of long runs of homozygosity, shared ancestry with later Neolithic populations, a sex bias in archaeozoological remains, and demographic profiles from across all layers of Ganj Dareh support management of genetically domestic goat by circa 8200 cal BC, and represent the oldest to-this-date reported livestock genomes. In these sites a combination of high autosomal and mtDNA diversity, contrasting limited Y chromosomal lineage diversity, an absence of reported selection signatures for pigmentation, and the wild morphology of bone remains illustrates domestication as an extended process lacking a strong initial bottleneck, beginning with spatial control, demographic manipulation via biased male culling, captive breeding, and subsequently phenotypic and genomic selection.
伊朗西部扎格罗斯山脉的无陶器新石器时代(约公元前 9600 年至 7000 年)提供了一些最早的考古证据,表明大约公元前 8200 年就开始管理和饲养山羊,大约 1000 年后才出现可检测到的形态变化。为了研究初始管理的基因组印记及其对山羊驯化过程的影响,我们分析了来自两个这样的遗址(甘杰达雷和特佩·阿卜杜勒·侯赛因)的 14 个新核基因组(平均覆盖度 1.13X)和 32 个线粒体(mtDNA)基因组(平均覆盖度 143X)。这些基因组显示出两个不同的聚类:那些具有家养亲和力的和少数具有更强野生亲和力的,这表明在这个早期阶段,管理的山羊在基因上与野生山羊不同。这种遗传二元性、长的纯合性运行、与后来新石器时代群体的共同祖先、考古动物学遗骸中的性别偏差以及甘杰达雷所有层的人口统计特征都支持大约公元前 8200 年对基因上的家养山羊进行管理,并且代表了迄今为止报道的最古老的家畜基因组。在这些遗址中,高常染色体和 mtDNA 多样性的结合,与有限的 Y 染色体谱系多样性形成对比,缺乏对色素沉着的报道选择特征,以及骨骼遗骸的野生形态表明,驯化是一个缺乏强烈初始瓶颈的扩展过程,从空间控制开始,通过偏向雄性的淘汰、圈养繁殖进行种群数量的人为操纵,随后是表型和基因组选择。