Aizpurua-Iraola Julen, Marí-Cardona Elisa, Barber-Olives Maria, Comas David, Calafell Francesc
Departament de Medicina i Ciències de la Vida, Institut de Biologia Evolutiva (CSIC-UPF), Universitat Pompeu Fabra, Dr. Aiguader 88, Barcelona, 08003, Catalonia, Spain.
Departament de Medicina i Ciències de la Vida (MELIS), Universitat Pompeu Fabra, Barcelona, Spain.
Sci Rep. 2025 Jan 3;15(1):660. doi: 10.1038/s41598-024-84271-w.
Ibiza (Eivissa) is one of the main Balearic Islands in the western Mediterranean. Recent studies have highlighted the genetic distinctiveness of present-day Eivissans within the region and suggested it could be attributed to the genetic drift caused by recent demographic events. Whether this distinctiveness emerged from a differential demographic history, or rather from a bias for sampling in a small geographic region such as Eivissa, remains an open question, together with the understanding of the functional consequences of demography in the island. In order to clarify these questions and further characterize the distinctiveness of Eivissa within the Balearic and Mediterranean context, we generated whole exome sequences for 31 and 20 individuals from Eivissa and Menorca respectively, a subset of which were also genotyped with the Human Origins array. Our results show that Eivissans present signs of putatively recent genetic isolation that are shared to a lesser extent with Menorca such as more and longer runs of homozygosity and high numbers of intra-population shared IBD segments. Regarding the functional consequences of recent demography, although Eivissans do not present an excess of deleterious alleles or homozygotes comparing to other populations, genetic drift seems to have increased the allele frequencies of neutral and deleterious variants, which can have various medical implications.
伊维萨岛(西班牙语称“伊维萨”)是西地中海主要的巴利阿里群岛之一。最近的研究突出了当今伊维萨岛居民在该地区的基因独特性,并表明这可能归因于近期人口事件导致的基因漂变。这种独特性是源于不同的人口历史,还是仅仅源于在伊维萨岛这样一个小地理区域抽样的偏差,仍是一个悬而未决的问题,同时对该岛人口统计学的功能后果的理解也尚不明确。为了澄清这些问题,并进一步刻画伊维萨岛在巴利阿里群岛和地中海背景下的独特性,我们分别为来自伊维萨岛和梅诺卡岛的31名和20名个体生成了全外显子组序列,其中一部分个体还使用人类起源阵列进行了基因分型。我们的结果表明,伊维萨岛居民呈现出近期基因隔离的迹象,梅诺卡岛居民在较小程度上也有类似迹象,比如纯合子片段更多、更长,以及群体内共享的同源染色体片段数量较多。关于近期人口统计学的功能后果,尽管与其他群体相比,伊维萨岛居民没有出现有害等位基因或纯合子过多的情况,但基因漂变似乎增加了中性和有害变异的等位基因频率,这可能会产生各种医学影响。