Tanaka S, Tojo H, Kasai K, Sawasaki T, Tachi C
Department of Applied Genetics, Graduate School of Agricultural Sciences, University of Tokyo, Japan.
Pigment Cell Res. 1994 Jun;7(3):152-7. doi: 10.1111/j.1600-0749.1994.tb00043.x.
Dominant black-eyed white phenotypes are one of the most commonly observed traits in domestic animals. Their genetic control mechanisms, however, have not been elucidated. As the first step to approach the problem, we examined histologically the patterns of the distribution of pigment cells in Shiba goats (two each of day-73-postcoitum and day-112-postcoitum fetuses, and a 15-week-old kid) with the dominant black-eyed white phenotype. Melanocytes were present and fully pigmented in the choroid and the sclera of eyes, as well as in dorsal skin epidermis of the fetuses and of the kid. Melanocytes were also found in approximately 6% of the hair bulbs in the fetal dorsal skin, while the rest (94%) lacked them. Hair follicles of the kid did not harbor melanocytes except for some in the early anagen stage. The results suggest that the survival of melanocytes was inhibited specifically in the hair follicles of the Shiba goat with the dominant black-eyed white phenotype and that the ostensibly similar phenotypes in the Shiba goat and in the S1 or W mutants of the mouse, where melanocytes die en route to the hair bulbs, are regulated by different mechanisms.
显性黑眼白毛表型是家畜中最常见的性状之一。然而，其遗传控制机制尚未阐明。作为解决该问题的第一步，我们对具有显性黑眼白毛表型的柴山羊（妊娠73天和112天的胎儿各两只，以及一只15周龄的幼羊）的色素细胞分布模式进行了组织学检查。在胎儿和幼羊的脉络膜、巩膜以及背部皮肤表皮中存在黑素细胞且色素沉着充分。在胎儿背部皮肤约6%的毛囊中也发现了黑素细胞，而其余（94%）则没有。幼羊的毛囊除了处于生长期早期的一些毛囊外，均未含有黑素细胞。结果表明，具有显性黑眼白毛表型的柴山羊毛囊中黑素细胞的存活受到特异性抑制，并且柴山羊与小鼠S1或W突变体中表面上相似的表型（黑素细胞在到达毛囊途中死亡）受不同机制调控。
