School of Biological Sciences, University of Utah, Salt Lake City, Utah, USA.
Evol Dev. 2021 Nov;23(6):477-495. doi: 10.1111/ede.12395. Epub 2021 Dec 16.
Deciphering the genetic basis of vertebrate craniofacial variation is a longstanding biological problem with broad implications in evolution, development, and human pathology. One of the most stunning examples of craniofacial diversification is the adaptive radiation of birds, in which the beak serves essential roles in virtually every aspect of their life histories. The domestic pigeon (Columba livia) provides an exceptional opportunity to study the genetic underpinnings of craniofacial variation because of its unique balance of experimental accessibility and extraordinary phenotypic diversity within a single species. We used traditional and geometric morphometrics to quantify craniofacial variation in an F laboratory cross derived from the straight-beaked Pomeranian Pouter and curved-beak Scandaroon pigeon breeds. Using a combination of genome-wide quantitative trait locus scans and multi-locus modeling, we identified a set of genetic loci associated with complex shape variation in the craniofacial skeleton, including beak shape, braincase shape, and mandible shape. Some of these loci control coordinated changes between different structures, while others explain variation in the size and shape of specific skull and jaw regions. We find that in domestic pigeons, a complex blend of both independent and coupled genetic effects underlie three-dimensional craniofacial morphology.
解析脊椎动物颅面变异的遗传基础是一个具有广泛进化、发育和人类病理学意义的长期生物学问题。颅面多样化最引人注目的例子之一是鸟类的适应性辐射,在这种辐射中,喙在它们的生活史的几乎所有方面都起着至关重要的作用。家鸽(Columba livia)为研究颅面变异的遗传基础提供了一个极好的机会,因为它在单一物种中具有独特的实验可及性和非凡的表型多样性之间的平衡。我们使用传统和几何形态计量学来量化源自直嘴波美拉尼亚凤头鸽和弯嘴斯堪德伦鸽品种的 F 实验室杂交后代的颅面变异。通过结合全基因组数量性状位点扫描和多基因座建模,我们确定了一组与颅面骨骼复杂形状变异相关的遗传基因座,包括喙形状、脑壳形状和下颌形状。其中一些基因座控制着不同结构之间的协调变化,而另一些基因座则解释了特定头骨和下颚区域的大小和形状的变化。我们发现,在家鸽中,三维颅面形态是由独立和耦合遗传效应的复杂混合所决定的。