Extreme Genetics

[colemaj]

I noticed that the majority of snake breeding takes the Mendellian genetics model. While this model rocks, it's incomplete. What begs the question and is the subject of this post, is the possibility for using crossing over to make new morphs. No John Edwards, this is some fun science.

Alright, So the way crossing over works, is that one gene spontaneously switches to it's sister chromosome during meitosis. So what's that mean to you?

If you have two gene's on the same chromosome, they often appear together. We'll say Blue eyes and the gene to make a leucistic. It's possible that the same gene codes for both(in the case of mojaves) but if you look at the Black Eyed Leucistics that fireballs produce. I might have those backwards, but the idea remains. Blue eyes and White scales might be two different genes. It's possible then that one of the genes would cross over and move to a normal chromosome, not containing say, the leucistic gene. So now you have one gene with leucism, one with the blue eyed trait. Your off spring winds up being a black eyed leucistic when you expected a blue eyed leucistic. If this happens, then one of the normals that popped out would have a recessive gene for blue eyes, and no genes for mojave. Breeding this guy to a blue eyed leucistic would produce .50 blue eyed normal, .50 blue eyed mojave. Wild eh?

The next question is, is this really possible and how likely. The answer depends on the distance the blue eyed gene is from the leucistic gene on the chrosome. The farther they are away, the more likely crossing over becomes. If they're close, the chance diminishes but is still there. So, if you're lucky enough to get a black eyed when you expected blue... you can likely make a really awesome new morph. I don't know a whole lot about different morphs that express two different genes, but if you guys think of any, try thinking of th possibilities and ways to breed it out.


Let me know what you think, or if anyone has heard of the blue eye trait missing.

[KCBALLer]

that's all sweet in theory, but waht are the odds of that actually happening? obviously it hasn't happened yet. Or has it? i mean who's to say that a spider wasn't originally a spider at all. at one point and time it was something else, but since it "crossed over" the new sper gene took dominance and the other died out. this is really something exciting to think about. how sweet would a blue eyed killer clown look? i never thought of this.

[colemaj]

The odds depend on the distance apart the genes are in the chromosome... the best way to prove this would be to breed blue eyed leucistics and black eyed leucistics. If you produce black eyed leucistic children, they would all be black eyed leucistic, and bred those children and got 1/2 blue eyed leucistic 1/2 black eyed leucistic you'd prove that the blue eyed gene is separate.... Then it's just a matter of time before blue eyeds bred together produce a black eyed or mojaves produce a black eyed. The other offspring would be the key to isolating the recessive blue eyed gene.

[Gloryhound]

Only one way to find out and that is try! It would be cool to seperate the blue gene. I believe they are having trouble seperating the two traits platty daddy has also. It appears that he has a co-dom gene of the lesser platnim, but also some sort of hypo that I'm not sure if Ralph has been able to get it to show without the lesser gene pressent. Also with that gene it sounds as if it is hard to make additional platty daddies as the birthings don't seem to follow the odds!

[colemaj]

If they don't follow the odds, what's probably happening is the genes are far apart on the chromsome and thus very likely to split off. It could be as likely as 50%, beyond that it'd be indistinguishable from different chromosomes... If you know a way I could get ahold of ralph, I'd be glad to send him some info about it.

[colemaj]

If the platty has a few recessive genes at work, it could even be multiple it's possible that when it's bred these genes scatter and you wind up with bizarre offspring. Multiple genes on the same chromosome produce results that are much unlike punnet squares predict.

[colemaj]

I was actually thinking wrong... each sperm would have a chance of crossing over... so you might have what appears to be a mojave or a normal carrying the blue eyed recessive gene....Basically breeding offspring to leucistics might one day produce a Blue eyed snake with an isolated gene..

Fantastic.

[elusivereptiles]

This sounds along the lines of Ralph Davis' "Platty Daddy" and his so called "hidden gene" and the same with NERD's woma's. Some of them carry a hidden gene which is why NERD's woma - Lesser pastel (http://www.newenglandreptile.com/ava...&cat=46&page=1) looks so much different than any others. Could it be that this wild gene is what you are talking about, and it only appears once it's overlapped so to speak?

[Gloryhound]

If the platty has a few recessive genes at work, it could even be multiple it's possible that when it's bred these genes scatter and you wind up with bizarre offspring. Multiple genes on the same chromosome produce results that are much unlike punnet squares predict.

The Lesser morph is from the off spring of "Platty Daddy". The super form of the lesser is the blue eyed Leucistics! This extra ressesive gene could be why the super form looks the way it does! A lesser could possibly prove out to be a dom by itself if recessive genes that can be seperated from the lesser are proven to exist. Also the last time I checked the only way Ralph was able to make more Platty Daddies was to breed a lesser born directly from platty daddy to a normal looking off spring from platty daddy. I read somewhere that only 3 platty daddies had been made, but I think the publication was a 2006 release, but can not really remember. One way to possibly get the blue eyed gene by itself could possibly to breed two normal looking offspring from "Platty Daddy" together.

Just maybe Ralph has already done this and is trying to get this gene mixed with other morphs to give him a head start in using this gene before he releases the base gene into the public. Wouldn't that just be something a top notch breeder like Ralph to have going on in some back room!

[muddoc]

What begs the question and is the subject of this post, is the possibility for using crossing over to make new morphs. No John Edwards, this is some fun science.

If this happens, then one of the normals that popped out would have a recessive gene for blue eyes, and no genes for mojave. Breeding this guy to a blue eyed leucistic would produce .50 blue eyed normal, .50 blue eyed mojave. Wild eh?

Let me know what you think, or if anyone has heard of the blue eye trait missing.

This is a very excellent post, and I think it could bring about some very intersting debate. I understand the theory of "crossing over", however, I have a slight problem with your description above. If crossing over is not using Mendalian theory, then how could you end up with said normal that is Recessive for Blue eyes. If it is recessive, then it is following Mendalian theory.

That covered my issue, but as for the rest of the thread, I think that we could eventually seperate some traits from Ball Pythons for varying reasons, including, to eliminate a "bad" gene, or to put one trait with another, as described in your example. I think if we had some contact with a genetics lab, we could possibly make a Spider that didn't carry the spinning trait, a Caramel that didn't carry the kinking trait. a Green eyed Leucistic, or even possibly a Super Spider (if it is indeed lethal).

Thanks for the thought provoking thread so early in the morning. It usually takes me longer to get the gears turning.