Cargill Edward J, Famula Thomas R, Schnabel Robert D, Strain George M, Murphy Keith E
Department of Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843, USA.
BMC Vet Res. 2005 Jul 26;1:1. doi: 10.1186/1746-6148-1-1.
The distinctive coat pattern of a Dalmatian is the result of the interaction of several loci. While the encoded function of these genes is not fully understood, it is known the Piebald, Ticking, and Flecking loci interact to produce the Dalmatian's classic pigmented spots on a white background. The color of the pigmented spots in purebred Dalmatians can either be black or liver, but the locus responsible for color determination is unknown. Studies have been conducted to determine the underlying genes involved in coat color determination in the dog, e.g., in the Labrador Retriever, but none to date have addressed black versus liver in the Dalmatian.
A genome scan was conducted in a multi-generational kindred of Dalmatians segregating black and liver spot color. Linkage analysis was performed using a total of 113 polymorphic microsatellite markers from the kindred. Linkage was found between spot color and a single microsatellite marker, FH2319 (LOD = 12.5) on chromosome 11.
The TYRP1 (Brown) locus is located at position 50.1 Mb on chromosome 11, which is approximately 0.4 Mb from marker FH2319. Given the recent characterization of TYRP1 genetic variations in the dog and the linkage evidence reported here, TYRP1 is likely responsible for the spot color variation of black versus liver seen in the Dalmatian.
大麦町犬独特的被毛图案是多个基因座相互作用的结果。虽然这些基因的编码功能尚未完全明确，但已知花斑、斑点和雀斑基因座相互作用，在白色背景上产生大麦町犬经典的色素沉着斑点。纯种大麦町犬色素沉着斑点的颜色可以是黑色或肝色，但负责颜色决定的基因座尚不清楚。已经开展了一些研究来确定犬类被毛颜色决定所涉及的潜在基因，例如在拉布拉多寻回犬中，但迄今为止还没有研究涉及大麦町犬黑色与肝色的问题。
在一个多代的大麦町犬家族中进行了基因组扫描，该家族中黑色和肝色斑点颜色呈分离状态。使用来自该家族的总共113个多态微卫星标记进行连锁分析。发现斑点颜色与11号染色体上的一个微卫星标记FH2319（LOD = 12.5）之间存在连锁关系。
TYRP1（棕色）基因座位于11号染色体上50.1 Mb的位置，距离标记FH2319约0.4 Mb。鉴于最近对犬类TYRP1基因变异的特征描述以及此处报道的连锁证据，TYRP1可能是导致大麦町犬黑色与肝色斑点颜色变异的原因。
