These are the offspring ratios we would expect, assuming we performed the crosses with a large enough sample size. If a genetic trait is recessive, a person needs to inherit two copies of the gene for the trait to be expressed.
Each member of the pair becomes part of the separate sex cell. Epistasis can be reciprocal: either gene, when present in the dominant or recessive form, expresses the same phenotype. A hybrid organism is one that is heterozygous, which means that is carries two different alleles at a particular genetic position, or locus.
Epistasis in mouse coat color: In mice, the mottled agouti coat color A is dominant to a solid coloration, such as black or gray.
Genes may also oppose each other with one gene modifying the expression of another. When the genes A and B are both homozygous recessive aabbthe seeds are ovoid.