23. Interaction between genes Flashcards
(6 cards)
1
Q
What happens in gene interaction?
A
When two or more genes influence the same phenotype, two genes can interact to determine one trait.
2
Q
What is epistasis?
A
A genotype at one gen locus masks the phenotypics expression of the alleles of another gene locus
3
Q
What is dominant epistasis?
A
Two genes A/a and B/b being inherited. If you have an A- this masks the effect of the alleles at the B/b locus
4
Q
What is the ratio for dominant epistasis?
A
For the F2 the phenotypic ratio is 12:3:1
- or exception 13:3 when one of the non epistasis phenotypes is the same as the epistasis one
5
Q
What can give a 9:7 ratio?
A
When only dominant A- and B- give a colour and anything else is colour less
6
Q
What are the other phenotypic ratios for gene interaction?
A
9: 3:4
9: 6:1
15: 1
