Coat colour in dogs: identification of the merle locus in the Australian shepherd breed.
Coat colour in dogs: identification of the merle locus in the Australian shepherd breed.
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DOI：
10.1186/1746-6148-2-9
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发表时间：
2006-02-27
影响因子：
2.6
通讯作者：
André C
中科院分区：
文献类型：
--
作者：
Hédan B;Corre S;Hitte C;Dréano S;Vilboux T;Derrien T;Denis B;Galibert F;Galibert MD;André C
犬科动物的毛色有许多天然的表型变异。一些相关的基因和等位基因也会导致遗传发育缺陷，这也在人类和小鼠中观察到。我们研究了狗的陨石色表型的遗传基础，以阐明色素沉着机制，并确定参与这些复杂途径的基因。陨石色表型包括缺乏真黑色素沉着和发育缺陷，听力障碍和小眼。这与在小眼畸形小鼠突变体中观察到的相似。利用狗作为一个强大的遗传模型，并利用最近可用的基因组资源，我们调查了分离的陨石色表型在五代血统，包括96个采样的澳大利亚牧羊犬。遗传连锁分析使我们能够确定一个位点的陨石色表型，跨越5.5兆碱基，在犬染色体10（CFA 10）的着丝粒尖端。在重组分数θ = 0时，Lod评分为15.65，支持该基因座。在其他三个品种的连锁分析显示，同一地区是连锁的山鸟色表型。该区域与人12号染色体（HSA 12 q13-q14）正交，属于人和小鼠基因组中保守的有序区段，并且包含可能涉及色素沉着和发育的几个基因。这项研究已经确定了狗的陨石色被毛位于CFA 10的着丝粒末端。对分离山鸟色表型的其他品种的遗传学研究应该允许更准确地定义基因座，目的是识别基因。这项工作显示了犬系统在寻找哺乳动物色素沉着和发育途径的遗传基础方面的力量。
Coat colours in canines have many natural phenotypic variants. Some of the genes and alleles involved also cause genetic developmental defects, which are also observed in humans and mice. We studied the genetic bases of the merle phenotype in dogs to shed light on the pigmentation mechanisms and to identify genes involved in these complex pathways. The merle phenotype includes a lack of eumelanic pigmentation and developmental defects, hearing impairments and microphthalmia. It is similar to that observed in microphthalmia mouse mutants. Taking advantage of the dog as a powerful genetic model and using recently available genomic resources, we investigated the segregation of the merle phenotype in a five-generation pedigree, comprising 96 sampled Australian shepherd dogs. Genetic linkage analysis allowed us to identify a locus for the merle phenotype, spanning 5.5 megabases, at the centromeric tip of canine chromosome 10 (CFA10). This locus was supported by a Lod score of 15.65 at a recombination fraction θ = 0. Linkage analysis in three other breeds revealed that the same region is linked to the merle phenotype. This region, which is orthologous to human chromosome 12 (HSA12 q13-q14), belongs to a conserved ordered segment in the human and mouse genome and comprises several genes potentially involved in pigmentation and development. This study has identified the locus for the merle coat colour in dogs to be at the centromeric end of CFA10. Genetic studies on other breeds segregating the merle phenotype should allow the locus to be defined more accurately with the aim of identifying the gene. This work shows the power of the canine system to search for the genetic bases of mammalian pigmentation and developmental pathways.