Hepp Diego, Gonçalves Gislene Lopes, Moreira Gilson Rudinei Pires, de Freitas Thales Renato Ochotorena
From the Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp, Gonçalves, and de Freitas); Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile (Gonçalves); Departamento de Zoologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Moreira); and Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp).
J Hered. 2016 Nov;107(6):544-52. doi: 10.1093/jhered/esw037. Epub 2016 Jun 9.
Different pigmentation genes have been associated with color diversity in domestic animal species. The melanocortin 1 receptor (MC1R), agouti signaling protein (ASIP), tyrosinase-related protein 1 (TYRP1), and v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) genes are candidate genes responsible for variation in wool color among breeds of sheep. Although the influence of these genes has been described in some breeds, in many others the effect of interactions among genes underlying wool color has not been investigated. The Brazilian Creole sheep is a local breed with a wide variety of wool color, ranging from black to white with several intermediate hues. We analyzed in this study the influence of the genes MC1R, ASIP, TYRP1, and KIT on the control of wool color in this breed. A total of 410 samples were analyzed, including 148 white and 262 colored individuals. The MC1R and ASIP polymorphisms were significantly associated with the segregation of either white or colored wool. The dominant MC1R allele (E(D) p.M73K and p.D121N) was present only in colored animals. All white individuals were homozygous for the MC1R recessive allele (E(+)) and carriers of the duplicated copy of ASIP A gene expression assay showed that only the carrier of the duplicated copy of ASIP produces increased levels in skin, not detectable in the single homozygous copy. These results demonstrate that the epistatic interaction of the genotypes in the MC1R and ASIP gene is responsible for the striking color variation in the Creole breed.
不同的色素沉着基因已与家畜物种的毛色多样性相关联。黑皮质素1受体（MC1R）、刺鼠信号蛋白（ASIP）、酪氨酸酶相关蛋白1（TYRP1）和v-kit哈代-朱克曼4型猫肉瘤病毒癌基因同源物（KIT）基因是导致绵羊品种间羊毛颜色差异的候选基因。尽管这些基因的影响已在一些品种中有所描述，但在许多其他品种中，羊毛颜色潜在基因间相互作用的影响尚未得到研究。巴西克里奥尔羊是一个当地品种，羊毛颜色多种多样，从黑色到白色，还有几种中间色调。在本研究中，我们分析了MC1R、ASIP、TYRP1和KIT基因对该品种羊毛颜色控制的影响。共分析了410个样本，包括148只白色个体和262只有色个体。MC1R和ASIP多态性与白色或有色羊毛的分离显著相关。显性MC1R等位基因（E(D) p.M73K和p.D121N）仅存在于有色动物中。所有白色个体均为MC1R隐性等位基因（E(+)）的纯合子，且是ASIP A基因重复拷贝的携带者。基因表达分析表明，只有ASIP重复拷贝的携带者在皮肤中产生增加的水平，在单拷贝纯合子中无法检测到。这些结果表明，MC1R和ASIP基因中基因型的上位相互作用是克里奥尔品种显著颜色变异的原因。
