Corso Josmael, Hepp Diego, Ledur Mônica C, Peixoto Jane O, Fagundes Nelson J R, Freitas Thales R O
Departmento de Genética, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul (IFRS), Porto Alegre, RS, Brazil.
Genet Mol Biol. 2017 Jan-Mar;40(1):104-108. doi: 10.1590/1678-4685-GMB-2016-0136. Epub 2017 Mar 20.
Domestic turkeys present several color phenotypes controlled by at least five genetic loci, but only one of these has been identified precisely: the bronze locus, which turned out to be the melanocortin-1 receptor (MC1R) gene. MC1R variation is important for breeders interested in maintaining or developing different color varieties. In this study, we sequenced most of the MC1R gene from 16 White Holland (the main commercial turkey variety) and 19 pigmented turkeys from southern Brazil with two purposes. The first was to describe the MC1R diversity in White Holland turkeys, which may serve as reservoirs of genetic diversity at this locus. The second was to test whether the traditional color classification used by Brazilian breeders is related to previously known MC1R alleles. White Holland turkeys had four different haplotypes corresponding to the bronze (b+) and black-winged bronze (b1) alleles. Pigmented turkeys also had four haplotypes corresponding to the b+ and b1 alleles, but different haplotypes represent the most common b+ allele in these two groups. The black (B) allele was absent from our samples. Overall, our results suggest that white and pigmented individuals form two different populations, and that the traditional color classification used by Brazilian breeders cannot accurately predict the genotypes at the bronze locus.
家火鸡呈现出几种受至少五个基因位点控制的颜色表型，但其中只有一个已被精确鉴定：青铜位点，结果证明它是黑皮质素-1受体（MC1R）基因。MC1R变异对于有兴趣维持或培育不同颜色品种的育种者来说很重要。在本研究中，我们对来自16只白荷兰火鸡（主要的商业火鸡品种）和19只来自巴西南部的有色火鸡的大部分MC1R基因进行了测序，目的有两个。第一个目的是描述白荷兰火鸡中MC1R的多样性，其可能作为该位点遗传多样性的储存库。第二个目的是测试巴西育种者使用的传统颜色分类是否与先前已知的MC1R等位基因相关。白荷兰火鸡有四种不同的单倍型，对应于青铜（b +）和黑翅青铜（b1）等位基因。有色火鸡也有四种对应于b +和b1等位基因的单倍型，但不同的单倍型代表了这两组中最常见的b +等位基因。我们的样本中没有黑色（B）等位基因。总体而言，我们的结果表明白色和有色个体形成了两个不同的群体，并且巴西育种者使用的传统颜色分类不能准确预测青铜位点的基因型。
