Why incomplete dominance name given to blending?

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Incomplete dominance refers to a genetic scenario where the phenotype of the offspring is a blend of the traits from both parents, while co-dominance occurs when both parental traits are fully expressed in the offspring. The discussion highlights a confusion regarding the terminology, questioning why only intermediate inheritance is labeled as incomplete dominance despite both concepts lacking complete dominance of a single trait. It is suggested that both incomplete dominance and co-dominance could be categorized under a broader definition of incomplete dominance, but traditional definitions remain distinct. The conversation emphasizes the importance of understanding the underlying mechanisms rather than solely relying on terminology, noting that phenotypes from genetic crosses may not clearly indicate the mechanisms at play. Additionally, there is an acknowledgment that definitions in genetics can be arbitrary and evolve over time.
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In incomplete dominance we say that trait expressed in F₁ is mixture of parents trait and in co dominance both the traits are expressed.
Now problem is that even in co dominance their is not complete dominance of any trait so why do we call only intermediate/mosaic inheritance as incomplete dominance.
It makes sense to me if we say both of these fall in category of incomplete dominance but it is not the case as we call only mosaic inheritance as incomplete dominance.
Thanks
 
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Probably for your exam, you should learn the terms as you were taught.

See if you like this: https://www.ncbi.nlm.nih.gov/books/NBK21920/
Roughly, incomplete dominance is used when the dominant allele produces something (a "dose"), and the recessive allele produces nothing. The idea is that the "standard" dominant/recessive situation is due to haplosufficiency, and incomplete dominance is modified haplosufficiency.
Co-dominance is used when both alleles produce something.

I do think these terminological distinctions are not that helpful. I do think the understanding in terms of mechanism is important and helpful. However, I don't think one can generally tell the mechanism from the phenotypes of various crosses.

Some more viewpoints here:
https://doi.org/10.1590/S0100-84551997000400018
https://dx.doi.org/10.1371/journal.pbio.1001356
 
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atyy said:
Probably for your exam, you should learn the terms as you were taught.

See if you like this: https://www.ncbi.nlm.nih.gov/books/NBK21920/
Roughly, incomplete dominance is used when the dominant allele produces something (a "dose"), and the recessive allele produces nothing. The idea is that the "standard" dominant/recessive situation is due to haplosufficiency, and incomplete dominance is modified haplosufficiency.
Co-dominance is used when both alleles produce something.

I do think these terminological distinctions are not that helpful. I do think the understanding in terms of mechanism is important and helpful. However, I don't think one can generally tell the mechanism from the phenotypes of various crosses.

Some more viewpoints here:
https://doi.org/10.1590/S0100-84551997000400018
https://dx.doi.org/10.1371/journal.pbio.1001356
Thanks sir,
I will memorize their name and understand what's going on in the Crosses,earlier also I have been earlier told that our definitions are arbitrary and change with time and are not perfect.
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