In rats, the P gene allele for pigmentation (P) is dominant to the allele for albinism (p). The B gene allele for black pigmentation (B) is dominant to the allele for cream pigmentation (b). The pp homozygous recessive genotype is epistatic to any allele combination at gene B.
-Predict the phenotypic ratio of the F₂ progeny of a parental cross between a pure-breeding black rat and an albino that is also homozygous for cream.