,

Incomplete dominance, Multiple Alleles

Codominance,

Codominance "co-" is "together". Refers to a relationship between two

alleles of a gene. Both traits appear in an organism. They do not overpower each other. Ex: spotted dog, two different colored eyes, pink and white flower.

Incomplete dominance A cross between organisms with two

different phenotypes produces offspring with a third phenotype that is a of the parent’s traits. 

Ex: RED Flower x WHITE Flower ---> PINK Flower

Blending

Multiple Alleles allele = (n) a form of a gene

which codes for one possible outcome of a phenotype.

Ex. Fur color = B=black, b=white Multiple means that one gene can

have many alleles. Ex: Blood type = A, B, AB, O.

Blood types:

BloodType

Caucasians

African American

Hispanic Asian

O + 37% 47% 53% 39%O - 8% 4% 4% 1%A + 33% 24% 29% 27%A - 7% 2% 2% 0.5%B + 9% 18% 9% 25%B - 2% 1% 1% 0.4%

AB + 3% 4% 2% 7%AB - 1% 0.3% 0.2% 0.1%

 

GENOTYPES IA IA IA i

RESULTING PHENOTYPES

Type A Type A

IB IB IB i

Type B Type B

IA IB Type AB

i i Type O

Examples:

I A I A I A I B

I A i I B i

I A I B x I A i

I A I B

I A

iGenotypes: Phenotypes:I A I A , I A i , I A I B , I B I A , AB, B 25 % 25% 25% 25% 50%, 25%, 25%