Ball Pythons and Incomplete Dominance

[Darcpixie]

The only way we have to determine ANYTHING with bp's is by breeding with other known morphs and comparing results. They are just allelic like the mojave/butter/lesser/het russo group, like ultra/amel. Two different mutations at the same locus, with similar but not identical effects.

Lemme check on something, but we referenced the mojave group as being all roughly the same, but the *blue eyed luecys* ARE different depending on which gene is used. Mojaves have GREY heads, for instance, and other forms DON'T... so while they are allelic, the supers are NOT identical.

Speaking of that, if you have ever bred fancy rats and heard of Megacolon, I BELIEVE that is going to be something similar, not in effect but in creation, to the spinner trait. Would be interesting to do an IN DEPTH pattern analysis of spiders and spinning to see if a particular pattern expression is related, as it is in fancy rats.

Just a thought.

While not breeding this year, I DO plan to breed bp's at some point, and have been doing morph research for about 6 months or so deciding on a female to pair with my Mojave male. So I haven't produced any, but boy, have I spent a LONG time perusing sites!

it would probably be worth it to arbitrarily assign letters to loci, and demonstrate which ones are resident on the same locus and which ones are not.

Then again, can be REALLY hard to tell with some breeders, since some just DON'T know what they have!

 

[TripleMoonsExotic]

Interesting about the rats. I'll have to read up on that!

The other thing with the Cinny/Black issue is that some Cinnys are so dark they appear Black and some Blacks are so light they appear Cinny. How probable is it that the genotype for these two are already misidentified in collections?

I really don't think, without genetic mapping, anyone can 100% say that Cinny and Black are different genotypes. Phenotypes, obviously, but not genotype. We're basing the information off of different breeders with different opinions.

 

[Darcpixie]

Yes, I did state that "Super" is a term used quite often for homozygous co-dom/inc-dom. That's not where I was trying to go with that, sorry. What I mean is that (as an example) in the Amel/Ultra allelic example we have an intermediate homozygous. Why would the homozygous of two different genotypes produce an animal that looks like the homozygous of each of the genotypes in question. Boy, does that sound confusing! Let me try wording it differently. Why does Cinny Homo, Black Homo and the Combo Homo all look nearly identical if they are different genotypes? Does that question make more sense? :laugh:

I did email NERD for clarification on their gallery page and for their opinion. I'll post their response if and when I get one.

I suppose they would look similar depending on whether it was a GOOD cinny (high amounts of blushing/brown) versus a BAD cinny?

I suppose we would need to doublecheck the parents for amount of blushing and see if that translates into a darker or lighter super-cinny?

Ah, the pain of ball python genetics

 

[toyah]

What I mean is that (as an example) in the Amel/Ultra allelic example we have an intermediate homozygous. Why would the homozygous of two different genotypes produce an animal that looks like the homozygous of each of the genotypes in question. Boy, does that sound confusing! Let me try wording it differently. Why does Cinny Homo, Black Homo and the Combo Homo all look nearly identical if they are different genotypes? Does that question make more sense?

The last question makes sense But just a note on the first part, a snake that has one ultra and one amel allele at the albino locus is NOT homozygous, by definition though - it is a heterozygous animal.

Homozygous cinnamon, homozygous black pastel, and heterozygous black pastel/cinnamon look very similar because the two alleles involved there, black pastel and cinnamon, are very similar mutations.

There is a documented example of this situation in mice (actually lots of them, but just one off the top of my head) - an AvyA mouse looks very much like a AhvyA mouse, and AvyAvy mice look similar to (but not the same as) AhvyAhvy mice which in turn are easily confused with AvyAhvy mice.

The fact that they can be difficult to distinguish doesn't mean they are the same ... they are very much different alleles. But it's reasonable to expect that similar looking allelic mutations will have similar forms when combined.

 

[Darcpixie]

If you want some MORE rat genetics pain, I can give you some. What I used to breed had downright WEIRD genetics, lol you can pm me if you want the run-down...

I BET that MANY of them are mis-identified in collections, ESPECIALLY since we are still importing them in mind-boggling quantities.

Not enough time to test breed to figure them out, probably, for some of them.

I mean goodness, you would almost have to wait until a particular animal was about 10 years old and had 7 breedings with different morphs to accurately determine what, specifically, it behaved as with each one and compare to known examples! That's assuming it's even a good example of whatever morph it is!

No one really does that, especially small scale breeders.... they tend to take how it was labeled and carry that over to its offspring.

*looks around for tylenol* Trying to square this stuff with even mendelian, SIMPLE genetics can give one a headache even if you're familiar with how it works! Who knows if each breeder has as good a grasp, or whether adults were proven or just *looked* like something!

Toyah... American mink and other color changes! like RED, american blue, and russian blue.... argh! so confusing!

 

[TripleMoonsExotic]

Well, NERD insists that Cinny and Black Pastel are identical in the genotype sense. They are one of the largest, well known breeders in the world. :shrugs:

This is an enquiry e-mail via http://www.newenglandreptile.com/nerd from:
Stephanie <[email protected]>

I have a genetics question based on the NERD Ball Python gallery...

Under Cinnamon it says "AKA Black Pastel" and under Black Pastel it says nothing comparable. First question is, is the "AKA Black Pastel" under Cinny a typo?

Along the same subject...Is NERD of the opinion that Cinny and Black Pastel are the same genotype but different lines (much like Pastel has different phenotypes based on the different lines)? Or do you think Cinny and Black Pastel are simply different genotypes that are allelic?

I look forward to your response!

[email protected] wrote:
Yes just like pastels, if they were different you would not be able to make a super from breeding a cinny to a black

 

[Darcpixie]

But their response doesn't honestly make sense. Then how can you breed a butter to a mojave and get a blue eyed leucy?

I would feel better about that answer if additional breeders were contacted.

 

[TripleMoonsExotic]

I didn't ask about Mojave. I asked about Cinny. But I'm writing up an email thanking them and I can ask their experience and opinion on the BEL producers as well.

What exactly don't you understand about their response?

I can contact Brian Sharp and Ralph Davis too if you like.

 

[Darcpixie]

Yes just like pastels, if they were different you would not be able to make a super from breeding a cinny to a black

The entire response. While comparing it to normal pastels squares with your opinion, the second one does NOT make sense with refuting the two genes that are allelic theory.

No one is questioning whether they are on the same locus and make a similar super. NOT identical, but similar.

As I said before, I'm not really certain why I'm debating this with you, as my opinion of the matter means very little. I disagree with both you AND NERD, and there is no need to answer the question to make ME happy.

Quoting VERBATIM off of Ralph Davis's site:

As of 2005..........the Cinnamon Pastel aka Black Pastel have both proved to be co-dom...the "Super Cinny" and "Super Black Pastel" are both dark chocolate colored patternless snakes. The "Pewter" from each line looks different to some degree...........Pewter being a Pastel x Cinny or a Pastel x Black Pastel...........the difference is not extreme in the Pewters..........also the "Supers" from each line are slightly different.........some say that one Super is darker than the other?.........more brown......more black.........

I have noticed many problems with the "Supers" from the year that they were first produced until now ( 05 ).........all that have been produced and that I have seen have face deformities....either elongated snouts.........thin cheeks and heads........a "turned up" snout.........kinks or twists..........I think to solve the problem with the Supers.........breeders need to NOT line breed to make the Supers...........bloodlines need to be mixed.

The "Super Pastel Cinny" aka Sterling Ball is from the Graziani Cinny Line..........the "Super Pastel Black Pastel" aka Silver Streak is from the Black Pastel line............these two snakes are "night and day" in appearance.............so I would think between the differences in the Supers, Pewters and "Super Pastel x Cinny/ Black" it's safe to say that the lines should be considered to do different things.

 

[TripleMoonsExotic]

They were comparing it to Pastel because I brought up how Pastels have distinct lines (Bell, Lemon, etc) and I wanted to be as clear as possible with what I was asking. They too are saying you wouldn't produce a Super with a Cinny and Black if they weren't the same genotype. :shrugs:

Honestly, if you read Ralph's description...It doesn't say anything about them being the same genotype, but does say about them being two different lines. I think that's one of the problems. "Line," to me at least, means selectively bred, but could mean genotype to someone else. All's we can do is ask for clarification.

If you aren't interested in the information I'm acquiring, then simply don't read it or respond. I really don't know what to tell you. :shrugs: I said I'd contact some of the top breeders to get their take instead of relying on forum posts and small time breeder opinion. What more can I do? :duck:

Either way, I'm email Brian and Ralph.

 

[TripleMoonsExotic]

Ralph was super quick to respond!

From: Triple Moons Exotic [mailto:[email protected]]
Sent: Thursday, May 14, 2009 9:14 PM
To: undisclosed-recipients:
Subject: Cinny / Black Pastel Genetics Question

As I'm sure you know, their is much talk online about Cinny and Black being different genotypes and allelic as opposed to the same genotype from different lines (like Pastels have Lemon, Bell, etc lines).
Generally when it's brought up it seems to me that the focus is on the phenotype with little regard to the actual genotype. I myself have made the argument that the heterozygous and homozygous of the two morphs are near identical as well as the super of the two when they're combined...Which supports Cinny and Black being the same genotype but two different selectively bred lines.

Also, what do you think of the BEL producers? Their are five mutations that produce the same phenotype in the super. It is possible that, like Pastel, Butter, Lesser, Mojave and Phantom are all the same genotype, they all look very similar...However, the wildcard would be the Russo's which are no where near the same phenotype as the other four...

I look forward to your response!

Ralph Davis wrote:
Cinnys and blacks are the same I would say.....both have produced the "tweaked" supers....

As far as blue eyed lucy......the super lesser and the super butter are whiter than the rest.......all similar........but the super lesser and super butter seem to be the whitest. Their eyes are bigger too.

Thanks,
Ralph

I asked for clarification on what he was saying about the Cinnys and this is his response:

Ralph Davis wrote:
I think they are the same thing....different lines

Thanks,
Ralph