In Dobermans the basic black and red color are associated with alleles at the B locus. The dominant allele, B, produces the black coat and the recessive genotype, bb, the red coat. To be fully expressed, the dominant allele, D, must be present at the dilution locus. In the presence of the dd genotype, black is diluted to "blue" and red diluted to "fawn." The relationship between genotype and phenotype is then: