Quote:
Originally Posted by JCCS
Co-dominant is where two dominant morphs "co-exist", creating a different phenotype, as in a hypo jungle or any other combination.
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Chris, I have never heard co-dom explained in that way before. I always understood co-dominance as an expression of one pair of genes, like dominant and recessive.
I tried to do a google search for what it would be called when two fully dominant genes are expressed (I would guess dual homozygous?) all I found was 'Mutually exclusive expression of two dominant genes'?; however on wikipedia, it lists the term 'codominance' as what you say it is (2 different dominant genes expressed) and then goes on to say "Co-dominance and incomplete or semi-dominance are not the same thing." ... meaning if there is a hyphen it has a different definition?
anyways, I usually defer to Paul Hollander, I found one of his posts on another site:
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"We have two sets of definitions of codominance and incomplete dominance in the quote.
<edit - he was quoting someone else's post in the thread..> (Semidominance is included under incomplete dominance.)
Set 1:
Incomplete dominance = the heterozygote shows a phenotype in between the homozygous recessive and homozygous dominant phenotypes.
Codominance = The two alleles of a pair at a specific locus are not identical but the expression of both is observed.
Set 2:
Incomplete dominance = One allele makes a product and the other does not, resulting in an intermediate phenotype.
Codominance = Both alleles make products, which may or may not produce an intermediate phenotype.
The second set shows that using an intermediate phenotype definition for incomplete dominance, as in the first set, is inaccurate. But we lack the data required to use the second set.
The result is continued disagreement.
The most honest course is admit that we can't tell the codominants from the incomplete dominants at this time. Then lump them together in a single category named codominants (or incomplete dominants or semidominants or whatever). That lets us continue business unchanged and finds us not guilty of the charge of laziness. A win-win solution, at least until someone steps up with a few million euros to fund a lab to get the necessary information. "
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post #42 at link:
http://www.redtailboas.com/f115/domi...tml#post508971
always willing to learn more! i am still a bit confused about it