Reptile & Amphibian Forums

www.vmsherp.com Genetics101, genetics 201, genetics 301, chromatophore biology, and mutations were decent reading.... of course I was specifically interested in what they said about hypomelanism and irridiphore dysfunction. The rest of the info was good as well.

Later,
Robert
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Great spirits have always been recieved with violent opposition by mediocre minds. Albert Einstein

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www.AlphaDragonZ.com

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Edited on January 29, 2005 at 10:00:55 by phwyvern.

It would make sense that they are T albinos... It is really the only way to explain the dark eyes without leucism being present. If that is true then from what I'm gathering from the link is that red is extremely prominant... Your glassy X candy cross should produce some KILLER "translucents" in a couple generations!

The only thing that still puzzles me about that is the fact that the white is almost absent in some specimens? It doesn't say anything about irridiphores reflecting or having anything to do with the white background so I wonder where the white comes into play at.... If leucism is a complete lack of pigmentation, then that would suggest that white isn't controlled by chromatophores and therefore really couldn't be a colorphase at all. Simply a lack of color but that still doesn't explain how hte white is removed in the translucents. Very intrigueing.

Later,
Robert
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Great spirits have always been recieved with violent opposition by mediocre minds. Albert Einstein

NP
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Great spirits have always been recieved with violent opposition by mediocre minds. Albert Einstein

Now that I reread this info, it seems that Seans breeding did prove something... (the snow leucistic hets) If the leucistic color is in fact a recessive gene... them it would have became the dominant "color" of the dragon. Since these hatchlings took on the appearance of the "Snow" gene it stands to reason that the lucys are a recessive form of hypomelanism as color has been bred into the lucy line.... the only other thing that it could be is that the hypo/snow line is a dominate form of hypomelanism that won out in appearance over the other recessive form of hypomelanism.

also if the clear nails were a seperate recessive trait from the hypopastel and lucy lines you would only get one beardie that showed both traits out of every 16 from a het to het breeding. Unless one of the traits is in fact co-dominate... in which case you'd get 25% hypomelanistic, 50% het for hypomelanistic and 25% normal and 50% of those would be homozygeous for clear nails as well... Right?

I realize I'm not breding these traits righ tnow but I find it all very fascinating and would like to get some feedback on what some of you think about this. It would help greatly to know what top expect from a breeding, especially when your giving 300 to 500 bucks apiece or more for your breeding stock.

Later,
Robert
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Great spirits have always been recieved with violent opposition by mediocre minds. Albert Einstein

Robert,
Well the first thing if you are looking at genetics and traits from a scientific point of you have to be extremely skeptic of everything you hear and people tell you. I believe that Sean made that assumption and rightfully so from Kevin's website that Leucistics come out completely white. How do you know that all marketed Leucistics come out white from the egg. Have you seen any marketed Leucistics hatch out? I would be willing to bet that most of them are not white at hatching. Maybe they are noticebly different then other "normal dragons" but still not completely white. I have seen several Leucistics from the source that are not completely white as described by the person who is selling them here in the U.S. Nost of them have some pastel or brown coloring around the eyes and head that fades as they become adults. I developed this opinion from actually looking at baby Leucistics that were 3-4 weeks old and observing Leucistic hatchling pics that people have sent to me and posted. How can you without seeing Sean's animals come to a conclusion based on what he is telling you they look like. The differene is a fine shade. Also dragons especially white ones can show vastly different coloration in diffferent settings. Many Snows can look very white like Brandon's Snow Dragons who have produced some super light offspring out of the egg. Some of his snow are whiter than many Leucistics. This could be husbandry, environmental, genetics or several other things.

Now that I reread this info, it seems that Seans breeding did prove something... (the snow leucistic hets) If the leucistic color is in fact a recessive gene... them it would have became the dominant "color" of the dragon.

I am not sure how you came to this conclusion. If you have to hets for Leucistic assuming that Leucistic is a reccesssive trait like Kevin says then if you breed two of those together then you would get 25% Homozygous recessive for both clear nails and Leucism, which would be considered a Leucistic. The rest would be 66% hets.

I think that you are assuming that there is a Codominant gene that Snows carry that is one of the possible alleles that fits into the same loci and that actually "competes" for the same spot as a Leucistic gene. First of all you have to have proven genetic traits to assert that conclusion. The Snow Dragons have not been proven to be any type of genetic trait. It would be very hard to prove unless you obtained some wild type beardies actually from the wild and then also obtained some Snows from the wild or that you know are not carrying any other hypo genes and then bred them for many generations to be certain what is going on with a possible "Snow gene." The reptiles that you are getting your background from are still being collected from the wild and therefore have proven wild types that they can use as a reference for breeding. But for BDs you cannot do the same. If Snows did carry a gene that was some form of Hypopmelanism then how would you prove it with a shallow mixed up gene pool. There is no way to tell that an animal is carrying a "Snow Codominant Gene" or not. It is for this reason that it is much easier to breed for straight recessive genes in BDs. They can be proven in a two or three generations where as codominant genes take many more generations and very distinct differences between Codominant traits. Leucistic and Snows do not have very distinct phenotypic differences. Look up Codominant genes in Chickens ,Which are "gene wise" closely related to Reptiles, and you will see that the Heterozygous Codominants have completely different phenotypic appearances than either Homozygous siblings in almost every study.

Clear nails can appear on both Hypomelanistic dragons and ones that are not. There are now several examples that I can site. Whether or not these clear nails from Hypomelanistic animals are the same genetic trait that shows up in Non Hypo animals remains to be seen. I do know that when I breed my Hypopastels to a Het Hypopastel that I get about 55-60% with clear nails and the rest with light brown to dark nails. When I do a Het to Het breeding I get about 33% with Clear nails.

Good talking to you and got to go to work to check out some fecals.
-Randy
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www.AlphaDragonZ.com

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Edited on January 29, 2005 at 10:02:04 by phwyvern.

Thanks for the reply and your thoughts! I'd never really looked at it from that point of view before.... BUT....lol... To say that it is impossible is in my opinion a little rash... i mean I can see that it could see how you'd think that but my opinion differs... The way I see it is that if there is a white hatchling that pops up in a clutch of normals who has clear nails and none of the other hatchlings display this trait whatsoever it is definately a genetic mutation. Whether it is passed on dominately, co-dominately, recessive, polygenically, or a colorphase that can be selectively bred I agree has yet to be determined. It is my opinion that there is either dominance or possibly co-dominance at work. Either way I have also formed the opinion that it definately has something to do with melanophore disfunction. That opinion comes from seeing how this trait works in many differant breedings by not only myself but many others.

As far as being skeptical... I'm there now.....lol.... But Ihave to add that I've also been following the lucys for well over a year now and I have also noticed the brownish color you spoke of in many pictures posted by many differant people.... that same color is even present in the hypo-pastel X lucy crosses...... and how do you know I haven't seen pics of Seans hatchlings? I have. and in my opinion they do appear more like a snow hatchling than any lucy baby pics I've seen. the brown coloration that fades suggests to me that this is a hypomelanistic mutation in the lucys.

Abotu Brandons snows.... If I remeber correctly, that is the snow line started from yet another whiote clearnailed dragon that popped up in a clutch of normals and was started by Chris who actually sold her to Brandon I believe... and did you notice in those breedings that the color crosses with her actusally held thier color? Why? Maybe the melanaphore disfunction is just a little bit differant because this mutation is from seperate bloodlines... that's my guess. It woulkd also explain why the snows are whiter as well. As far as proving a mutations genes to be co-dominate?.... not impossible... co-dominate mutations in reptiles (let's not jump to chickens just yet lol) manifest differantly species to species... there is one that the heterozygoues offspring are VERY similar to the homozygoues.... there is also a codominate gene that can produce two seperate heterozygoues phenotypes andwhen bred to another het of the same phenotype produce a dominate/homozygeous phenotype but when the two seperate phentypes are bred together they produce....LEUCISTICS......that is very cool and very exciting!!! So though it may be harder to prove... it is p[ossible without a wildtype speciman.... I mean how would you know that the wild type speciman didn't have some form of hypomelanism lurking? It has already been proven that the snow trait is passed on to the F1 generation and that would suggest either a dominant or codominate trait .....as well as an inherited or possibly even a polygenic trait.

As for the clear nails.... If you have two seperate recessive genes.... an animal het for both would be a double het and to get them to ap,pear in the same animal would be a 1 in 16 shot.....then you would have hypos het for clear nails, clearnaileds het for hypo, double hets, etc.

However, I have some eggs hatching and one appears to have clearnails and doesn''t appear hypo at all yet. It's hard to tell but when I hold him up to the light... I can't see any black in the nails at all and I can in the others that have hatched so I guess we'll see in a few weeks when they aren't 3.5" long....LOL

Thanks again for the healthy conversation and new point of view......Like I said this is very interesting to me and I really enjoy chatting about it!

Hope the fecals didn't give you too much trouble...LOL

Later,
Robert
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Great spirits have always been recieved with violent opposition by mediocre minds. Albert Einstein

that's 2 out of 4 so far.... The father..... a zillafroggy X redflame sandfire red from Chris Allen, had clear thumb nails when I recieved him and the rest of his nails are clear with the black across the top of the nail if that in fact signifies anything.... Like I said it's really hard to tell, but exciting to me just the same!

Later,
Robert
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Great spirits have always been recieved with violent opposition by mediocre minds. Albert Einstein