Aykanat Tutku, Debes Paul V, Jansouz Shadi, Gueguen Lison, House Andrew H, Ruokolainen Annukka, Erkinaro Jaakko, Pritchard Victoria L, Primmer Craig R, Bolstad Geir H
Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki 00014, Finland.
Department of Aquaculture and Fish Biology, Hólar University, Sauðárkrókur 550, Iceland.
G3 (Bethesda). 2025 Jul 9;15(7). doi: 10.1093/g3journal/jkaf106.
Understanding pleiotropic architectures of phenotypes is instrumental for identifying the functional basis of adaptive genetic variation in the wild. Life-history variation may have a morphological basis that mediates resource acquisition allocation pathways, but identifying the underlying genetic basis of such traits is challenging. Using Atlantic salmon (Salmo salar) juveniles reared in common garden conditions, we test if 2 life-history associated loci, six6 and vgll3, are also associated with functional morphological traits. These loci had previously shown to exhibit strong signals of adaptation and are highly correlated with sea age at maturity. We show that genetic variation at the vgll3 locus is linked to variation in morphological traits that underlie swimming performance, along a tradeoff axis between efficient cruising and maneuvering, while the genetic variation at the six6 locus was linked to variation in body-head proportions suggesting the potential functional importance of these traits for resource acquisition efficiency. However, the direction of changes in morphological traits associated with late- vs early maturing alleles was not always consistent with the expected direction of an effect to maturation timing. Our results reveal a complex morphological landscape associated with the genetic variation in these loci, possibly as a result of pleiotropy or linkage across these genomic regions.
了解表型的多效性结构有助于识别野生环境中适应性遗传变异的功能基础。生活史变异可能具有介导资源获取分配途径的形态学基础，但确定此类性状的潜在遗传基础具有挑战性。我们利用在共同环境条件下饲养的大西洋鲑（Salmo salar）幼鱼，测试两个与生活史相关的基因座six6和vgll3是否也与功能性形态性状相关。这些基因座此前已显示出强烈的适应性信号，并且与成熟时的海龄高度相关。我们发现，vgll3基因座的遗传变异与构成游泳性能基础的形态性状变异相关，存在于高效巡航和机动性之间的权衡轴上，而six6基因座的遗传变异与身体头部比例的变异相关，表明这些性状对资源获取效率具有潜在的功能重要性。然而，与晚熟和早熟等位基因相关的形态性状变化方向并不总是与对成熟时间影响的预期方向一致。我们的结果揭示了与这些基因座的遗传变异相关的复杂形态景观，这可能是由于这些基因组区域的多效性或连锁造成的。
