Non-allelic Interactions Flashcards
Two or more independent genes present on the same or different chromosomes interact to produce a new expression
Non-allelic Interactions
Non-allelic Interactions
- Novel Phenotype
- Complementary Gene Action
- Duplicate Gene Action
- Recessive Epistasis
- Dominant Epistasis
F2 Phenotypic Ratio of Novel Phenotype
9:3:3:1
___ phenotype result from interaction between _____; also from interaction from _____ _____
- New
- dominants
- homozygous recessive
Example of Novel Phenotype
- Chicken Comb
- Lentil: seed coat color
Novel Phenotypes can arise from the combined action of ___ of __ ___
Alleles of Two Genes
In novel phenotype, how many phenotypes in F2?
4 distinct F2 Phenotypes
- there is complete dominance of both gene pairs; but either recessive
- homozygote is epistatic to the effects of the other gene
Complementary Gene Action
F2 Phenotypic Ration of Complementary Gene Action
9:7
Complementary Gene Action: ___ ____ allele of each of ___ ____ is necessary to produce ____
- one dominant
- two genes
- phenotype
Example of Complementary Gene Action
- Petal color in flowers
- Sweet Pea flower coloration
There is complete dominance at both gene pairs, but either gene when dominant, is epistatic to the other
Duplicate Gene Action
F2 Phenotypic Ratio of Duplicate Gene Action
15:1
Example of Duplicate Gene Action
Shape of seen capsule in Shepherd’s purse
There is complete dominance at both gene pairs, but one gene when homozygous recessive, masks the effect of the other
Recessive Epistasis
F2 Phenotypic Ratio of Recessive Epistasis
9:3:4
Recessive Epistasis: _____ recessive of one gene ____ both ____ of another gene
- Homozygous
- masks
- alleles
Example of Recessive Epistasis
- Coat color in mice
- Onion Bulb colors
- Retreiver: coat color
What is the basis of epistasis in mouse coat color?
Clear when the biochemical pathway is considered
It is modified black hair with yellow stripes
Agouti hair
The pigment that produces stripe yellow hair or red
Pheomelanin (Phaeomelanin)
What is the function of the wild-type agouti gene product?
To switch from eumelanin to phaeomelanin
What is Epistasis?
When the alleles of one gene masks the expression of alleles of a second gene
There is complete dominance at both gene pairs, but one gene, when dominant masks the effect of the other
Dominant Epistasis 1
F2 Phenotypic Ratio of Dominant Epistasis 1
12:3:1
Dominant Epistasis 1: _____ allele of one gene _____ effects of _____ ____ of another gene
- dominant
- hides
- both alleles
Example of Dominant Epistasis 1
Fruit color in squash
- there is complete dominance at both gene pairs, but one gene when dominant, is epistatic to the second
- the second gene when homozygous recessive, is epistatic to the first
Dominant Epistasis 2
F2 Phenotypic Ratio of Dominant Epistasis 2
13:3
Dominant Epistasis 2: ____ alleles of one gene ____ effects of ____ ____ of another gene
- Dominant
- hides
- dominant allele
Example of Dominant Epistasis 2
Feather color in Fowl
