Data from: The genetic basis of discrete and quantitative colour variation in the polymorphic lizard, Ctenophorus decresii

Background: Colour polymorphic species provide invaluable insight into processes that generate and maintain intra-specific variation. Despite an increasing understanding of the genetic basis of discrete morphs, sources of colour variation within morphs remain poorly understood. Here we use the polymorphic tawny dragon lizard Ctenophorus decresii to test simple Mendelian models for the inheritance of discrete morphs, and to investigate the genetic basis of continuous variation among individuals across morphs. Males of this species express either orange, yellow, orange surrounded by yellow, or grey throats. Although four discrete morphs are recognised, the extent of orange and yellow varies greatly. We artificially elevated testosterone in F0 females and F1 juveniles to induce them to express the male throat colour polymorphism, and quantified colour variation across the pedigree. Results: Inheritance of discrete morphs in C. decresii best fit a model whereby two autosomal loci with complete dominance respectively determine the presence of orange and yellow. However, a single locus model with three co-dominant alleles for orange, yellow and grey could not be definitively rejected. Additionally, quantitative expression of the proportion of orange and yellow on the throat was strongly heritable (orange: h² = 0.84 ± 0.14; yellow: h² = 0.67 ± 0.19), with some evidence for covariance between the two. Conclusions: Our study supports the theoretical prediction that polymorphism should be governed by few genes of major effect, but implies broader genetic influence on variation in constituent morph traits.背景：体色多态物种为揭示物种内变异的产生与维持机制提供了极为宝贵的研究视角。尽管学界对离散体色形态的遗传基础已有愈发深入的认知，但同一形态内部的体色变异来源仍有待阐明。本研究以多态性棕尾岩龙蜥（Ctenophorus decresii）为研究对象，一方面检验离散形态遗传的经典孟德尔模型，另一方面探究不同形态个体间连续体色变异的遗传基础。该物种雄性喉部可呈现橙色、黄色、黄围橙（橙色被黄色环绕）或灰色四种离散形态；尽管已明确划分四种形态，但橙色与黄色的覆盖范围存在显著差异。我们通过人为提升F0代雌性及F1代幼体的睾酮水平，诱导其呈现雄性特有的喉部体色多态性，并对整个家系的体色变异进行了量化分析。 结果：棕尾岩龙蜥离散形态的遗传模式最符合如下模型：两个具完全显性效应的常染色体位点分别控制橙色与黄色性状的表达。不过，由三个共显性等位基因（分别对应橙色、黄色与灰色）构成的单位点遗传模型，仍无法被完全排除。此外，喉部橙色与黄色占比的量化表型具有较高的遗传力（橙色：h²=0.84±0.14；黄色：h²=0.67±0.19），且二者间存在一定的遗传协变证据。 结论：本研究验证了"体色多态性由少数主效基因调控"的理论预测，同时也表明组成该形态的性状变异受到更为广泛的遗传影响。