Cow retic is an example of a recessive and an inc-dom making a visual combo iirc. (Het Oraange Ghost Stripe and Phantom)
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Oh damn, your right. That’s a great example.
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Strongly disagree. By that metric would you also consider Pied inc-dom?
Personally, I strongly agree with both of them being incomplete dominants.
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I don’t believe the epistatic relationship of mutations are at all governed by our ability to visually identify them in heterozygous/homozygous form. Great example with the cow retics.
In this hobby/market in particular I think we often overestimate our understanding and prematurely conclude definitive functions and interactions of various mutations. The complexity of it all is part of what makes it so interesting and fun.
Is clown/pied/etc a form of dominance or recessive? What percentage of visually identifiable characteristics must be obvious before a recessive mutation is redefined as inc. dominant? 100%? 50%? 1%?
Could some sort of intermediate label that describes a recessive mutation that is sometimes identifiable visually in heterozygous form be appropriate? Even if it doesn’t exist in the scientific world it might be helpful in our hobby. Maybe that’s some form of scientific blasphemy :). Either way, it’s fun to discuss and speculate!
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If a heterozygous trait is visual, then it cannot be recessive.
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There has been quite a bit of double, triple, and quad+ recessive combinations being produced recently. Interestingly, experienced breeders are stating it has an effect on visual phenotype.
A particular quad het clutch from Always Evolving Pythons comes to mind, sunset/pied/clown/lavender albino. Miguel and J.Kobylka noted how they do not look like typical normals. I dont recall all the characteristics but I think they came out much brighter and more colorful. Recessive mutations, by definition, should not do that. Maybe it’s all a little more complex than we realize.
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On this one I can see pied being incomplete dominant. I have seen in my own collection a common phenotype expression in my het pieds I have produced. But I’m not totally convinced on it either lol.
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I agree and from a scientific standpoint I think both clown and pied are inc-dom. However, I fear that if they were labeled as inc-dom in the hobby people would wrongly label snakes and guess or inaccurately identify if they are het or not.
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So take my anwer with a grain of salt because I just woke up and haven’t had coffee yet, but I do believe it’s possible.
Allelic refers to the fact that the variants that make up the morphs in question are at the same loci in the genome, it does not mean they are the same type of variant. For example one could be a duplication of a gene and one could be a deletion. This would suggest that clown could be inc-dominant while cryptic remains recessive depending on the nature of variant in question and dosage effects of the gene necessary to alter phenotype
I feel like falls into the category of unlikely, but technically possible
Also, I think het clowns are more visually identifiable, much more so than het pieds. I realized this when sorting through hundreds of pictures for the machine learning morph ID program I was working on a few years ago.
And now I will sit back and patiently wait for Travis to arrive and tell me I’m wrong 
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Considering that we all know that clown and pied can make visual changes in Het form, how can we be sure that’s it’s not just the combo of Het Clown + Het Pied? We also haven’t seen anywhere near the volume of Het Sunsets as we have those two. For all we know Sunset falls into the same low key inc dom category. Until the more scientific and less financially driven breeders in the community give it a whirl, we won’t really know.
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Great point.
I would think the financial incentive of the early market would have been enough to determine whether pied or clown are a form of dominance. If it was visually identifiable in heterozygous form with any consistency breeders would have stood to gain many thousands of $$$. People investing 10k+ in a het and breeding it to their normals (or whatever) sure would have loved to be able to pick out those hets.
With the quad het sunset/clown/pied/lav clutch, for example, I think every animal came out looking obviously different. It seems likely that if the cause was from just one mutation or two it would have been identified much earlier in the market when financial incentives were much higher from those single mutation animals. There’s speculation that the stacking of so many particular recessive mutations could be to blame. Lavender has also been observed to create brighter hets. Could all of them combined be a factor? Either way, it all goes against the established idea that hets from a recessive mutation can never be identified visually. Are they not “recessive” after all? Is there more going on that we just dont understand yet? Not sure, but I circle back to my question: With what consistency do hets have to be clearly identifiable before it moves from recessive to inc. dominant? I’ve never heard a definitive answer on that.
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Agree with this. Simplification, even over-simplification, of these terms is better for the hobby at large. Het. ‘markers’ are already an abused idea without reassigning these muations as inc-dom. Not all track lines are indicators of Het Pied etc… The list goes on.
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Whenever I see the T replying I usually know I’m wrong lol
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Why does everyone think I live to just prove them wrong? Am I that wrathful??
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Alright… A lot to unpack here
This is accurate. Mostly.
Let me give a hypothetical to illustrate
Dominant type mutations (both simple dominant and incomplete-dominant) are almost exclusively a dominant negative type of mutation. Which is to say a change to the code that results in a negative effect because the product is expressed. So think of it like you are building a barrel and you have two machines that make the slats. If one of the machines starts cutting slats wrong, then even though you have good slats from one machine, you end up with a leaky barrel because some of the bad slats are going to end up in each barrel and so the barrel longer fits together properly.
Recessive type mutations are almost exclusively a loss of function type of mutation. Which is to say a change to the code that results in a no product being expressed. In this situation, one of your slat making machines fails completely. You still end up making normal barrels because the other machine is still making perfectly good slats.
Now… Here is where things get different and why I put in my “mostly” caveat above. What happens when we look at homozygosity in both situations and in the compound heterozygote?
Looking at the inc-dom scenario, both of your machines are now cutting slats wrong. You still build a barrel, but whereas the “het” form of the barrel leaks a little, the homozygous form is more a sieve than it is a leaky barrel.
By contrast, looking at the recessive case, if both of your machines are broken you can never build a barrel.
So what does the compound heterozygote look like?
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It looks like the homozygous inc-dom. Because the only slats available are the incorrect ones.
Bring this back to our conversation of Cryptic and Clown. If Clown were inc-dom and Cryptic were recessive, then the Crypton would look like a Clown. Which it very obviously does not.
Now, I am not saying Clown is not inc-dom. I am just saying that Clown and Cryptic are not disparate mutation types.
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Disagree, though very unpopular opinion every time I have brought it up (and I am not getting in to that argument again here, I just do not have it in me today)
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No blasphemy at all. There is a valid scientific genetics term (except it is applied to dominant type mutations that are sometimes not expressed, as opposed to recessives that are). That term is incomplete penetrance
But if you think that it would cause confusion to try relabeling het Pied as inc-dom, then consider the apocalyptic bedlam it would cause to try and re-educate the entire hobby about a mostly obscure genetics term… I mean, I have only been fighting the “codom” misinformation for two decades… 
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An astute observation and one that dovetails nicely with the below
So…
I have long been vocal that the paradoxical nature of our labeling of some genes as ‘recessive’ and others as ‘inc-dom’ has to do with when and how they were “discovered” in the hobby.
Pieds and Clowns came in as visual animals that were bred to normals and, because the babies were not anything drastically different like the other known, flagrantly blatant, inc-doms at the time like Pastel and Cinny, they were labeled as recessive.
Then someone bred two kind of slightly different looking animals together and made an Ivory. And all of the sudden, people realized that some stupidly subtly different looking animals might actually be the next new inc-dom. Thus began the era of the incredibly subtle inc-doms: Quake, Specter, Spark, etc
However, inertia on morphs earlier labeled as ‘recessive’ had already taken hold among the hobby at large and so no one bothered to reevaluate them.
Except…
A dirty little secret at the time is that certain big breeders had figured it out on their own and very purposefully kept that info close to their chest. Pete Kahl was heard on more than one occasion remarking that he loved the “poss het” game with Pieds because he could always pull the hets out of those clutches and keep them for himself and still sell the ones he knew were not hets for an inflated price.
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I’m skeptical, but you do seem very confident in your assertion. Would you be willing to test your ability to pick out het clowns from normals? I’ve grabbed four pictures of young ball python from the store. At least one of these is het clown with no other genes, and the other(s) are normals. Can you pick out which one(s) are het clowns?
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Oh I like this!
I’m stuck between 1 and 4.
The speckling in 1s alien head is more than I’m expecting so I say 4.
It’s gonna be number 3 
the one I’m least confident in. I’m no Kobylka or Ozzy though 
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I’m saying 3
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