Sarabia Carlos, Salado Isabel, Fernández-Gil Alberto, vonHoldt Bridgett M, Hofreiter Michael, Vilà Carles, Leonard Jennifer A
Center for Computational Molecular Biology, Brown University, Providence, Rhode Island, USA.
Estación Biológica de Doñana (EBD-CSIC), Seville, Spain.
Mol Ecol. 2025 Jun;34(12):e17639. doi: 10.1111/mec.17639. Epub 2025 Jan 10.
Invading species along with increased anthropogenization may lead to hybridization events between wild species and closely related domesticates. As a consequence, wild species may carry introgressed alleles from domestic species, which is generally assumed to yield adverse effects in wild populations. The opposite evolutionary consequence, adaptive introgression, where introgressed genes are positively selected in the wild species, is possible but has rarely been documented. Grey wolves (Canis lupus) are widely distributed across the Holarctic and frequently coexist with their close relative, the domestic dog (C. familiaris). Despite ample opportunity, hybridization rarely occurs in most populations. Here we studied the geographically isolated grey wolves of the Iberian Peninsula, who have coexisted with a large population of loosely controlled dogs for thousands of years in a human-modified landscape. We assessed the extent and impact of dog introgression on the current Iberian grey wolf population by analysing 150 whole genomes of Iberian and other Eurasian grey wolves as well as dogs originating from across Europe and western Siberia. We identified almost no recent introgression and a small (< 5%) overall ancient dog ancestry. Using a combination of single scan statistics and ancestry enrichment estimates, we identified positive selection on six genes (DAPP1, NSMCE4A, MPPED2, PCDH9, MBTPS1, and CDH13) for which wild Iberian wolves carry alleles introgressed from dogs. The genes with introgressed and positively selected alleles include functions in immune response and brain functions, which may explain some of the unique behavioural phenotypes in Iberian wolves such as their reduced dispersal compared to other wolf populations.
入侵物种以及日益增加的人类活动可能导致野生物种与亲缘关系较近的家养物种之间发生杂交事件。因此，野生物种可能携带来自家养物种的渗入等位基因，一般认为这会对野生种群产生不利影响。相反的进化结果，即适应性渗入，也就是渗入的基因在野生物种中受到正向选择，这种情况是有可能的，但鲜有记录。灰狼（Canis lupus）广泛分布于全北区，经常与其近亲家犬（C. familiaris）共存。尽管有充足的机会，但在大多数种群中杂交很少发生。在此，我们研究了伊比利亚半岛地理隔离的灰狼，它们在人类改造的景观中与大量管控松散的家犬共存了数千年。我们通过分析150个伊比利亚和其他欧亚灰狼以及来自欧洲和西伯利亚西部的家犬的全基因组，评估了家犬基因渗入对当前伊比利亚灰狼种群的程度和影响。我们发现几乎没有近期的基因渗入，总体上古时候家犬的血统比例较小（<5%）。通过结合单扫描统计和祖先富集估计，我们在六个基因（DAPP1、NSMCE4A、MPPED2、PCDH9、MBTPS1和CDH13）上发现了正向选择，野生伊比利亚狼携带从家犬渗入的这些基因的等位基因。携带渗入且受到正向选择的等位基因的这些基因涉及免疫反应和大脑功能，这可能解释了伊比利亚狼一些独特的行为表型，比如与其他狼群相比它们的扩散行为减少。
