(black)

1 AA : 2 Aa : 1 aa complete dom/rec dom dom rec incomplete dominance dom blend dom-rec rec codominant dom1 dom1+ dom2 dom2 recessive lethal (dom. marker) dead dom rec

1 gene with 2 alleles

we’ve seen 4 cases:

IA & IB are co-dominant; i is recessive

1 Gene with 3 alleles

IC. Genes with multiple alleles

Hierarchy of dominance:C > cch > ch > c

IC. Genes with multiple alleles

IC. Genes with multiple alleles

chinchillacch

IC. Genes with multiple alleles

chinchillacch

IC. Genes with multiple alleles

chinchillacch

himalayanch

Hierarchy of dominance:C > cch > ch > c

IC. Genes with multiple alleles

IC. Genes with multiple alleles

A short list of the 1587 known mutant alleles of the Drosophila melanogaster eye color gene w (white)

IC. Genes with multiple alleles

Back to 2 genes

TIME

ID. Two genes, interacting

ID. Two genes, interacting

A/A ; B/B

a/a ; b/b

A/a ; B/b self-cross

A/_ ; B_/

A/_ ; b/b

a/a ; B_/

a/a ; b/b

ww m+ & m

Coat color:Genes

A, B, C, D, E, S

A

AY

B

Ccc

C

C

D

E

E

II. Mention epistasis versus suppression

S

III.

Genotype -> Phenotype . . .but with interactions of unknown other genes, environment. . . + ,

Lack ofPenetrance

Variable Expressivity

Lack ofPenetrance

.4