Differences between incomplete dominance and codominance

Differences between incomplete dominance and codominance, hi guys in this article we try to understand what is incomplete dominance and codominance and what is main difference between incomplete dominance and codominance?

The law of dominance is not always found to be correct as there are many examples where the complete dominance is absent in such cases some traits of a F1 phenotype is intermediate between those of parental traits or both alleles shown its effects in F1 phenotype, first one is incomplete dominance and second one is codominance.

What is incomplete dominance? In incomplete dominance the genes of allelomorphic pair are not expressed as dominant and recessive but expresses themselves partially when present together in the hybrid. As a result F1 hybrid show characters intermediate to the effect of two genes of the parents. A good example of incomplete dominance is seen in mirabilis jalapa (4 o’clock plant) and Antirrhinum majus and it has also been notice in Andalusian fowl.

In Four o’clock plant when a cross is made between red flower (RR) and white flower (rr) variety, F1 hybrid produce is all pink flower (Rr). When these F1 pink flowers are self pollinated or cross among themselves to raise F2 generation they produce red (RR), Pink (Rr) and White flowers (rr) giving 1:2:1 Ratio. This phenotype ratio is identical with genotypic ratio because heterozygotes are phenotypically intermediate between two homozygous types.

What is codominance? When the dominant character is not able to suppress, even incompletely the recessive character and both the character appear side by side in F1 hybrid generation this phenomenon is known as codominance. In this case the F1 generation resembles both parents.

Common example of codominance is seen in cattles, if cattle with black coat is crossed to a cattle with white colour the F1 hybrid process Roan coat colour. In roan coat colour both black and white patches appear separately. The allele which are able to express themselves independently when present together are known as codominant allele.

What is difference between incomplete dominance and codominance? When F1 hybrid generation or individual which expresses intermediate between of two characters or do not expresses as dominant and recessive is term as incomplete dominance. Common example of incomplete dominance is Four o’clock plant. However in codominance both recessive and dominant characters appear side by side in F1 hybrid individuals, no one character is able to suppress even incompletely the recessive character. Common example of codominance is seen in cattles.

Differences between incomplete dominance and codominance

Now we briefly explain the differences between incomplete dominance and codominance to the point.

Incomplete dominance:-
1) in incomplete dominance the genes of allelomorphic pair are not expressed as dominant and recessive but Express themselves partially when process together in the hybrid as a result a F1 hybrid show characters intermediate to the effect of two genes of the parents.

2) one of the two allele shows more conspicuous effects

3) hybrid is the intermediate expression of two alleles

4) expression in hybrid is mixture of two allele

5) good example of incomplete dominance is 4 o’clock plant.

Codominance:-
1) when the dominant character is not able to suppress, even incompletely the recessive character and both the character appear side by side in F1 hybrid, the phenomenon is known as codominance. in this case the F1 generation resembles both parents.

2) both the allele shows equal effectiveness

3) both the allele show their affect independently.

4) no mixing takes place due to effect of two allele

5) good example of codominance is ABO blood group system.