García-Elfring Alan, Roffey Heather L, Abergas Jaren M, Hendry Andrew P, Barrett Rowan D H
Department of Biology, McGill University, Montreal, Quebec, Canada.
Biology Department, Vanier College, Montreal, Quebec, Canada.
Anim Genet. 2025 Apr;56(2):e70011. doi: 10.1111/age.70011.
Pterin pigments are responsible for many of the bright colors observed across the animal kingdom. However, unlike melanin, the genetics of pterin-based pigmentation has received relatively little attention in animal coloration studies. Here, we investigate a lineage of axanthic ball pythons (Python regius) found in captivity as a model system to study pterin pigmentation in vertebrates. By crowdsourcing shed skin samples from commercial breeders and applying a case-control study design, we used whole-genome pool sequencing (pool-seq) and variant annotation. We identified a premature stop codon in the gene GTP cyclohydrolase II (gch2), which is associated with the axanthic phenotype. GCH2 catalyzes the first rate-limiting step in riboflavin biosynthesis. This study provides the first identification of an axanthism-associated gene in vertebrates and highlights the utility of ball pythons as a model to study pterin-based pigmentation.
蝶呤色素是动物界中许多鲜艳颜色的成因。然而，与黑色素不同，基于蝶呤的色素沉着的遗传学在动物色彩研究中受到的关注相对较少。在此，我们研究了圈养环境中发现的无黄化球蟒（球蟒）谱系，将其作为研究脊椎动物蝶呤色素沉着的模型系统。通过从商业养殖者那里众包脱落的皮肤样本，并采用病例对照研究设计，我们使用了全基因组池测序（Pool-seq）和变异注释。我们在鸟苷三磷酸环化水解酶II（gch2）基因中鉴定出一个提前终止密码子，该密码子与无黄化表型相关。GCH2催化核黄素生物合成中的第一个限速步骤。这项研究首次在脊椎动物中鉴定出与无黄化相关的基因，并突出了球蟒作为研究基于蝶呤的色素沉着的模型的实用性。
