In a Certain Breed of Chicken, an Incomplete Dominant Gene

Essay

In a certain breed of chicken, an incomplete dominant gene controls color. The homozygous black (BB), when crossed with the homozygous splashed-white (bb), produces an intermediate gray color pattern referred to as blue. A second gene controls the shape of the comb. The dominant allele (R) produces rose, whereas the recessive allele (r) produces single. Give the F1 and F2 genotypic and phenotypic ratios of a cross between a true-breeding black with a single comb and a true-breeding splashed-white with a rose comb.