Polygenic traits vs codominance vs incomplete dominance (1 Viewer)

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Hi,

This is the answer to a question I saw in a thread about the difference between codominance vs incomplete dominance and where polygenic traits fitted into it. I am not sure where the thread went - if it was deleted or I just can't find it. Hope this helps!

Incomplete dominance occurs when the dominant alleles are not fully dominant hence the recessive can also be seen. An example of this is the pink snapdragon where both the white and red snapdragon flower alleles overlap with one another.

Codominance occurs when two dominant alleles are expressed at the same time. This can be seen in blood groups when an A and a B are both presents. This results in the blood type AB. Additionally, when red cows are bred with white cows, both hair colors are present in the offspring.

Polygenic traits are determined by multiple alleles for multiple genes that code for one trait. An example of this is skin color – this gives rise to an array of different colors and variations since it is more complex in inheritance.
 
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Eagle Mum

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Hi,

This is the answer to a question I saw in a thread about the difference between codominance vs incomplete dominance and where polygenic traits fitted into it. I am not sure where the thread went - if it was deleted or I just can't find it. Hope this helps!

Incomplete dominance occurs when the dominant alleles are not fully dominant hence the recessive can also be seen. An example of this is the pink snapdragon where both the white and red snapdragon flower alleles overlap with one another.

Codominance occurs when two dominant alleles are expressed at the same time. This can be seen in blood groups when an A and a B are both presents. This results in the blood type AB. Additionally, when red cows are bred with white cows, both hair colors are present in the offspring.

Polygenic traits are determined by multiple alleles that code for one trait. An example of this is skin color – this gives rise to an array of different color’s and variations since it is more complex in inheritance.
I really like your great explanations & examples of codominance and incomplete dominance, but polygenic traits are traits determined by more than one gene (eg. height, IQ). The term ‘multiple alleles’ refers to variations in the same gene, so pertains to a single gene rather than multiple genes.
 
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