I will not argue that 'snow' is a 3rd phenotype. I just tried to explain it that way to make it clear that the doubly homo. recessivity in the genotype is what is important.

OK, so we're now clear that the Snow is in fact a 3rd phenotype. I only overstated this point from my last post because you stated this "It isn't really a 3rd phenotype but rather the 2 phenotypes occurring at the same time."

The third phenotype IS NOT due to a 3rd genotype but rather a combination of 2 separate genotypes. There isn't a 'snow' gene.

I never stated that there was just a single gene for Snow.

I think you are a little confused about what a genotype actually is. A genotype is not a gene, instead, a gene is a part of a genotype. And a single gene does not necessarily make up a genotype either, it's generally a small part of many genes which make up a genotype although we usually do refer to genotypes based on simple Mendelian traits. Again, every source I can site will practically state the same thing: Genotype: 1)The entire set of genes in an organism. 2)A set of alleles that determines the expression of a particular characteristic or trait (phenotype)..

A snow is a snake that is both albino and axanthic at the same time.

Yes and no. A Snow is an animal that has both the Albino and Axanthic genes which make up an entirely new genotype that also creates a new phenotype. If you have a Snow that is also het for Lavender, it's phenotype will still be that of a Snow but it will then be another completely new genotype which is the entire set of genes it carries. However, I would greatly argue that a Snow is both an Albino and Axanthic, as it stands, as neither trait is visually discernible from it's phenotype. Like I stated previously, if you caught a Snow in the wild, there is no way you would come to the immediate conclusion that an animal like that has both genes for Albinism and Axanthism. You would only come to that conclusion after breeding trials. Again, this is why I suggested that the Snow, or Double Recessive Homo animals genotypes behave like those defined as Incomplete Dominant genotypes, it's the blending of colors. Now, if we had an animal that had a yellow dorsal base type but with charcoal dorsal saddles/patterns and it proved out to carry both the Albino and Axanthic genes, then I would suggest that this was working much like a Codominant trait as that is how Codominant traits tend to work versus the blending that happens in Incomplete Dominant traits.

I'll admit that saying that a Double Recessive Homozygous (DRH) animal, such as a Snow, is a bit of reach considering that the definition of an Incomplete Dominant trait is based on F1 animals coming from Dominant gene parents. But the visual end results for the DRH animal are the exact same which is why I made the comparison. If Incomplete Dominance was a bit more general about the blending of Homo traits instead of F1 Dominant based progeny, then I think it would be a no-brainer that this is are DRH animals are as well. But that's just my take on it.

Your superconda x normal example doesn't work since that is not a simple recessive character. You DO have 3 phenotypes related to 3 genotypes at a single locus.

I never stated that the Superconda was a Recessive gene nor did I state that it exhibits the traits of one. As I previously stated in my post on Codominance & Incomplete Dominance, I came to the conclusion that the Superconda gene is in fact a Codominant gene. I do believe that my example works because a Superconda, Anaconda and Normal all have completely different phenotypes which also directly coincides with 3 different genotypes (ie Superconda 'ss', Anaconda 'Ss' and Normal 'SS'). Again, a genotype is defined as "A set of alleles that determines the expression of a particular characteristic or trait (phenotype).". Isn't that what this is, a differing set of alleles for each animal that is expressing different phenotypes? I believe it is.

I am enjoying the discussion as well.... Any geneticists in the room?

I am too! I find this type of conversation mentally stimulating. Regardless of whether I'm correct in my assertions and/or assumptions, I am motivated to delve further in my current understanding of these topics so that I can address and at least comprehend to some depth what it is we are dealing with and talking about. Some people might be content with just knowing that you can eventually create a Snow by breeding an Albino and Axanthic together, but I want to know why. :D
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