Exploring neutral and adaptive processes in expanding populations of gilthead sea bream, Sparus aurata L., in the North-East Atlantic

Recent studies in empirical population genetics have highlighted the importance of taking into account both neutral and adaptive genetic variation in characterizing microevolutionary dynamics. Here we explore the genetic population structure and the footprints of selection in four populations of the warm-temperate coastal fish, the gilthead sea bream (Sparus aurata), whose recent northward expansion has been linked to climate change. Samples were collected at four Atlantic locations, including Spain, Portugal, France and the South of Ireland, and genetically assayed using a suite of species-specific markers, including 15 putatively neutral microsatellites and 23 Expressed Sequence Tag-linked (ESTs) markers, as well as a portion of the mitochondrial DNA (mtDNA) Control Region. Two of the putatively neutral markers, Bld-10 and Ad-10, bore signatures of strong directional selection, particularly in the newly established Irish population, though the potential 'surfing effect' of rare allele...

实证种群遗传学领域的近期研究强调，在解析微进化动态时，同步考量中性与适应性遗传变异至关重要。本研究针对暖温带近海鱼类金头鲷（Sparus aurata）的四个种群展开分析，探究其遗传种群结构与选择印迹——该物种近期的北向扩张与气候变化存在关联。研究样本采集自大西洋沿岸的四个采样位点，涵盖西班牙、葡萄牙、法国及爱尔兰南部；通过一系列物种特异性分子标记开展遗传分型检测，包括15个推定中性微卫星标记、23个表达序列标签连锁（ESTs）标记，以及线粒体DNA（mtDNA）控制区的一段序列。分析结果显示，其中两个推定中性标记Bld-10与Ad-10呈现出强烈的定向选择信号，尤以新近建立的爱尔兰种群最为显著，尽管稀有等位基因的潜在‘冲浪效应’……