What if the heterozygous trait exhibited codominance? in this case, two alleles can code for co-dominant traits. That is, neither is dominant over the other. Blood type is an example of this:
A is codominant to BA is dominant over O
B is dominant over O
Possible genotypes:
heterozygous AB blood gives both type A protein and type B protein on the erythrocytes.
homozygous AA gives blood type A protein on the erythrocytes
homozygous BB is blood type B protein on the erythrocytes
Heterozygous AO is gives blood type A
Heterozygous BO is blood type B
