In horses, A is an allele for the Bay phenotype when present along with E for
the black coat. The A allele does not effect chestnuts such that:
| A_E_ is Bay |
aaE_ is Black |
_ _ee is Chestnut |
The double blank in the chestnut genotype indicates any genotype at the A locus can exist there. The A allele can be considered a dominant epistatic allele to the EE or Ee genotype at the E locus in that the A allele dilutes the black color produced by eumelanin. Production of eumelanin occurs in horses having at least one E allele. Since the genotype, ee, produces no eumenlanin, no effect of the A allele is observed.
What is the ratio of progeny phenotypes expected from the following matings:
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