The "Extended Brown" Plumage Color Mutant of Blue-Breasted Quail () is Associated with a Mutation in the Melanocortin 1-Receptor Gene ().

The mutant plumage color "extended brown (EB)" of the blue-breasted quail was genetically investigated. Mating experiments revealed that the EB plumage is controlled by an autosomal, incompletely dominant allele, for which we propose the symbol The EB plumage is characterized by dark brown color, and homozygotes for this mutation generally showed darker pigmentation than the heterozygotes. DNA sequencing and PCR-RFLP analyses of the EB mutants showed a rigid association between the EB plumage and a G-to-A nucleotide substitution at position 274 in the melanocortin 1-receptor gene (), clearly indicating that is the candidate gene for the EB plumage color in the blue-breasted quail.