Lecture 3f: Non-Allelic Interactions

Question 1

the process by which the expression of two or more genes influences one another in different ways as an organism develops a single characteristic. The majority of the traits that comprise living beings are coordinated by various genes.

Answer 1

gene interaction

Question 2

an alternate form of a gene in which the alleles that affect a particular character are present at the same locus of the gene

Answer 2

allelic gene

Question 3

an alternate form of a gene in which the alleles that affect a particular character are present at different loci of the gene

Answer 3

non-allelic gene

Question 4

location: On the same location of the homologous chromosome
effects: Could form lethal genes and cause death

Answer 4

allelic gene

Question 5

gene interaction types of allelic genes

Answer 5

Incomplete dominance, lethal factor, multiple alleles, etc.

Question 6

location: On different locations of the homologous chromosome
effect: Could not affect phenotypes but cause an inhibitory effect on other non-allelic genes

Answer 6

non-allelic gene

Question 7

gene interaction types in non-allelic genes

Answer 7

Simple interaction, complementary factor, epistasis, inhibitory factor, etc.

Question 8

classical ratio of allelic/non-allelic gene interaction

Answer 8

3:1 or 9:3:3:1

Question 9

• Interaction between alleles at different genes (loci) can result in Epistasis
• Can have varying effects on the phenotype

Answer 9

Non-Allelic/Epistatic gene interaction

Question 10

Novel Phenotype ratio

Answer 10

9:3:3:1

Question 11

New phenotypes result from interaction between dominants; and also from interaction from homozygous recessives.

Answer 11

novel phenotype 9:3:3:1

Question 12

There is complete dominance of both gene pairs, but either recessive
homozygote recessive is epistatic to the effects of the other gene

Answer 12

complementary gene action 9 : 7

Question 13

complementary gene action ratio

Answer 13

9 : 7

Question 14

Homozygote is epistatic to the effects of the other gene.

Answer 14

complementary gene action 9 : 7

Question 15

duplicate gene action ratio

Answer 15

15:1

Question 16

There is complete dominance at both gene pairs, but either gene when dominant, is epistatic to the other

Answer 16

duplicate gene action 15:1

Question 17

There is complete dominance at both gene pairs, but one gene when homozygous recessive, masks the effect of the other

Answer 17

recessive epistasis 9:3:4

Question 18

recessive epistasis ratio

Answer 18

9:3:4

Question 19

There is complete dominance at both gene pairs, but one gene, when dominant masks the effect of the other.

Answer 19

Dominant Epistasis 12:3:1

Question 20

5. dominant epistasis ratio

Answer 20

12:3:1

Question 21

There is complete dominance at both gene pairs, but one gene, when dominant masks the effect of the other.

Answer 21

dominant epistasis

Question 22

6. dominant epistasis ratio

Answer 22

13:3

Question 23

• 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.

Answer 23

dominant recessive 13:3

Question 24

non-allelic gene interactions

Answer 24

1. novel phenotype (9:3:3:1)
2. complementary gene action (9:7)
3. duplicate gene action (15:1)
4. recessive epistasis (9:3:4)
5. dominant epistasis (12:3:1)
6. dominant epistasis (13:3)

Question 25

example of novel phenotype

Answer 25

chicken combs

Question 26

example of complementary gene action

Answer 26

petal colors in sweat pea flowers

Question 27

examples of recessive epistasis

Answer 27

• coat color in mice
• onion bulb color
• labrador dog coat color

Question 28

example of dominant epistasis (12:3:1)

Answer 28

fruit color in squash

Question 29

example of dominant epistasis (13:3)

Answer 29

feather color in fowl (chicken breeds)

Question 30

example of duplicate gene action

Answer 30

shape of seed capsule in Sheperd’s purse

Question 31

the inheritance of one gene does not influence the inheritance of the other gene.

Answer 31

law of independent assortment

Question 32

Each genotype results in a unique phenotype

Answer 32

novel phenotype

Question 33

At least one dominant allele from each of the two genes needed for phenotype

Answer 33

Complementary gene action

Question 34

Homozyous recessive genotype at one locus masks expression at second locus

Answer 34

recessive epistasis

Question 35

Dominant allele at one locus masks expression at second locus

Answer 35

dominant epistasis

Question 36

One dominant allele from either of two genes needed for phenotype

Answer 36

duplicate gene action