巴斯克人历史上一直生活在比利牛斯山脉西部,在佛朗哥-坎塔布里亚地区,横跨目前的西班牙和法国领土。在过去的几十年里,由于其独特的文化和生物学特征,它们一直是深入研究的焦点,争议很大,把它们作为异质的,孤立的,独特的人口。他们的非印欧语言,Euskara,被认为是塑造巴斯克人遗传景观的主要因素。然而,由于先前研究的局限性,关于他们的历史和假设的奇异性仍然存在激烈的争论。这里,我们在微观地理水平上分析了巴斯克和周围不讲Euskara的群体的全基因组数据。在1,970个现代和古代样本中,共分析了629,000个全基因组变异,包括来自巴斯克地区18个采样地点的190个新个体。第一次,从全基因组数据进行了局部和大规模分析,覆盖了整个佛朗哥-坎塔布里亚地区,结合等位基因频率和基于单倍型的方法。我们的结果表明,巴斯克人与周围人群有明显的区别,不讲Euskara的法语-Cantabrians处于中间位置。此外,观察到巴斯克人的遗传异质性与地理有显著的相关性。最后,与其他伊比利亚和周围人群相比,检测到的巴斯克人分化不能归因于外部起源。相反,我们表明,这种分化是铁器时代以来遗传连续性的结果,其特征是孤立的时期和最近缺乏基因流动,这些基因流动可能被语言障碍所加强。
Basques have historically lived along the Western Pyrenees, in the Franco-Cantabrian region, straddling the current Spanish and French territories. Over the last decades, they have been the focus of intense research due to their singular cultural and biological traits that, with high controversy, placed them as a heterogeneous, isolated, and unique population. Their non-Indo-European language, Euskara, is thought to be a major factor shaping the genetic landscape of the Basques. Yet there is still a lively debate about their history and assumed singularity due to the limitations of previous studies. Here, we analyze genome-wide data of Basque and surrounding groups that do not speak Euskara at a micro-geographical level. A total of ∼629,000 genome-wide variants were analyzed in 1,970 modern and ancient samples, including 190 new individuals from 18 sampling locations in the Basque area. For the first time, local- and wide-scale analyses from genome-wide data have been performed covering the whole Franco-Cantabrian region, combining allele frequency and haplotype-based methods. Our results show a clear differentiation of Basques from the surrounding populations, with the non-Euskara-speaking Franco-Cantabrians located in an intermediate position. Moreover, a sharp genetic heterogeneity within Basques is observed with significant correlation with geography. Finally, the detected Basque differentiation cannot be attributed to an external origin compared to other Iberian and surrounding populations. Instead, we show that such differentiation results from genetic continuity since the Iron Age, characterized by periods of isolation and lack of recent gene flow that might have been reinforced by the language barrier.