Jason,

You are correct in that I failed to clarify the P1 generation. Assuming that you are starting with a homozygous recessive sire bred to a homozygous dominant dam, your expected outcome would be all heterozygotes. Assuming a hetero to hetero breeding you would expect 1:2:1 (roughly) breakdown in phenotypes. Hetero to homozygous dominant would yield as you said a 50:50 mix of offspring (roughly).

You state that you "feel it is only possible to visually determine tha an hypo is not a homozygous hypo." Thus you are indicating that there is a distinct phenotypical difference between the homozygous dominant, heterozygous, and homozygous recessive state. Which is the definition of a codominant trait.

I guess we are going to have to agree to disagree on this one until we can prove out our test crosses. Coloration is a multiallelic trait and can be effected by so many different factors that we may never sort it out.

I'm just curious what the the phenotype breakdowns have been on the various states. What were the results of a hetero to homozygous dominant? What were the results of a hetero to hetero breeding?

As I mentioned, I'm just trying to understand the position that this is a dominant trait. If it were, you would expect to see it more often in wild populations than in the rare instances that it does occur.

Ian

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