TABLE 4.5 Modified dihybrid phenotypic ratios due to gene interaction
| Ratio* |
Genotype |
Type of interaction |
Example discussed in text |
| AA BA |
AA bb |
aaA BA |
aa bb |
| 9 : 3 : 3 : 1 |
9 |
3 |
3 |
1 |
None |
Seed shape and seed color in peas |
| 9 : 3 : 4 |
9 |
3 |
4 |
Recessive epistasis |
Coat color in Labrador retrievers |
| 12 : 3 : 1 |
12 |
3 |
1 |
Dominant epistasis |
Color in squash |
| 9 : 7 |
9 |
7 |
Duplicate recessive epistasis |
— |
| 9 : 6 : 1 |
9 |
6 |
1 |
Duplicate interaction |
— |
| 15 : 1 |
15 |
1 |
Duplicate dominant epistasis |
— |
| 13 : 3 |
13 |
3 |
_NBSP_ |
Dominant and recessive epistasis |
— |