Epistatic Interaction of the Melanocortin 1 Receptor and Agouti Signaling Protein Genes Modulates Wool Color in the Brazilian Creole Sheep.
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.
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). diego.hepp@gmail.com.
Diego
D
Hepp
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).
Gislene Lopes
GL
Gonçalves
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).
Gilson Rudinei Pires
GR
Moreira
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).
Thales Renato Ochotorena
TR
de Freitas
D054366:Agouti Signaling Protein / Q000235:genetics*; D000483:Alleles; D000818:Animals; D001938:Brazil; D001947:Breeding; D004843:Epistasis, Genetic; D015870:Gene Expression; D005787:Gene Frequency; D056726:Genetic Association Studies; D005838:Genotype; D006239:Haplotypes; D008297:Male; D010375:Pedigree; D010641:Phenotype; D010858:Pigmentation / Q000235:genetics*; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D044102:Receptor, Melanocortin, Type 1 / Q000235:genetics*; D012756:Sheep / Q000235:genetics*; D014935:Wool
D054366:Agouti Signaling Protein; D044102:Receptor, Melanocortin, Type 1
melanin receptors; native sheep; wool color genetics