RESUMEN
The melanocortin 1 receptor (MC1R) gene is a candidate functional gene that controls the pigment production in melanocytes. The aim of this study was to identify polymorphisms and investigate the effect of the MC1R gene on plumage coloration in duck breeds, including Korean native ducks. Initially, 34 individuals from seven duck breeds were sequenced, obtaining 12 polymorphisms. Five single nucleotide polymorphisms (SNPs) in the coding region were non-synonymous, with mutations corresponding to amino acid changes. Among these, four SNPs were genotyped using polymerase chain reaction-restriction fragment length polymorphism method in 264 individuals from same seven duck breeds. Fisher's exact test was conducted to identify possible relationships between the MC1R gene polymorphisms and plumage color variations. Four non-synonymous SNPs, c.52A>G (p.Lys18Glu), and c.376 A>G (p.Ile126Val), c.409G>A (p.Ala137Thr) and c.649C>T (p.Arg217Cys), were associated with the two deduced genotypes (i.e., E/E and e+ /e+) based on plumage color phenotypes. In addition, we reconstructed MC1R gene haplotypes, where the haplotype AAGC showed its highest frequency in Nageswari duck breed, which presents an extended black phenotype. Our results indicate that the identified polymorphisms by this study can be used to explore associations with plumage color variations in Asian duck breeds.