Unproven Dominant
You might be asking "Why have I never heard of this?" That would be because I made it up. I feel there is a need to differentiate between dominant morphs and the ones that are on the waiting list, which I call unproven dominant. A dominant morph has a visual change in the heterozygous form and the exact same change in the homozygous form. I define an unproven dominant as a morph having an unknown homozygous form. It might be a incomplete dominant/co-dominant morph that just hasn't proved out yet. It also could be a dominant morph. So what does it take to prove a dominant morph is in fact a dominant morph? I only know of two ways, statistics and complexes.
We will start with breeding a Pinstripe to another Pinstripe. The offspring statistically will be 25% Homozygous Pinstripe, 50% Heterozygous Pinstripe, and 25% Normal. Now since Pinstripe is a dominant morph, the homozygous and heterozygous forms look exactly the same. We are unable to tell them apart, so what we have is all the Pinstripes being 33% possible homozygous. 25% homozygous to 50% heterozygous which is a 1:2 ratio or 33% homozygous:66% heterozygous.
Now unlike possible recessive hets which can be proven out through producing visuals, we need to use statistics to prove homozygous dominant morphs. When the homozygous Pinstripe is bred, it will always produce Pinstripes. Once there have been enough eggs of all Pinstripes to call it something other than luck, you have proven it homozygous. One normal offspring will quickly prove the animal to be heterozygous. How many eggs you need to see is completely up for debate, but to give you the odds of a heterozygous Pinstripe producing all Pinstripes, here is a little chart.
# of eggs | Fraction | Percent |
---|---|---|
5 eggs | 1/32 | 3% |
10 eggs | 1/1,024 | .09% |
15 eggs | 1/32,768 | .003% |
20 eggs | 1/1,048,576 | .00009% |
25 eggs | 1/33,554,432 | .000003% |
I'm not sure where the community wants to draw the line, but things are looking good after 15 eggs if you ask me. To sum it up, it takes a lot of time, resources, and good record keeping to prove a single gene to be dominant.
If the unproven dominant gene is part of a complex, it can easily be proven by breeding two of the same complex morphs together. For example Daddy Gene is part of the same complex as Lesser Platinum. A Daddy Gene and Lesser Platinum sitting together makes a Platinum. Breed two Platinums togther and your left with straight forward odds 25% BEL, 50% Platinum, and 25% Homozygous Daddy Gene. Each of them are entirely different looking morphs, BEL being an all white snake with blue eyes, Platinums looking like hypo Lesser Platinum, and homozygous Daddy Gene looking just like the heterozygous Daddy Gene. All you have to do is hit that 25% chance and it makes it easy to say that the Daddy Gene is dominant.
Heterozygous | Homozygous | |
---|---|---|
Recessive | No Visible Change | Visible Change |
Co-Dominate/ Incomplete Dominant | Visible Change | Different Visible Change |
Dominant | Visible Change | Same Visible Change |
Unproven Dominant | Visible Change | ????? |