F2 phenotype ratio

Additive

9:3:3:1

Additive

2 separate genes, 1 unique trait, 4 genotypes

Recessive epistasis

9:3:4

Recessive epistasis

Golden retriever fur color black, chocolate, or epistatic yellow

Dominant Epistasis 1

Squash color, epistatic white, yellow, and green

Reciprocal recessive epistasis

9:7

Reciprocal recessive epistasis

Both genes must have a dominant allele to make purple

Dominant epistasis 1

12:3:1

Dominant epistasis 2

13:3

Dominant epistasis 2

Chicken fur, recessive color allele mimics dominant deposition allele

Redundancy

15:1

Redundancy

Leaf is green only when both are recessive