white bp's

[Scales Zoo]

I've been reading up on horse color genetics, and came across the following.

Taken from http://greenfield.fortunecity.com/dreams/799/hc/inheritance.htm


Palomino works a bit differently. Palomino requires a heterozygous arrangement of alleles at the C locus. The homozygous dominant CC will be chestnut, the homozygous recessive cc will be cremello, and the heterozygous Cc will be palomino. Since palominos have to be heterozygous, the color cannot breed true -- in other words, crossing a palomino with a palomino will only give you a 50% chance of a palomino foal, with a 25% chance of a chestnut and 25% chance of a cremello.


I realize mojave's and a few other co-dom (or dominant, or incomplete dominant - or whatever they really are) have produced white snakes when bred together.

Maybe it isn't the homozygous dominant (super) traits causing this, but the homozygous recessive traits (lack of any of the dominant traits - like the 1/4 normals one gets with pastel x pastel breedings)

With true dominants, (where the hets look like the homo's, or "supers") 3/4 of the clutch could all look mojave (or whatever), and 1 of those 3 would be a super mojave, but one wouldn't know till proving it out a few years down the road.

With true co-dominants (where the homo should look more different than the het), maybe the homozygous dominant looks pewter, or all black, or some snake we haven't seen yet, and it is the homozygous recessive that is actually responsible for the white snakes.

I imagine this has been brought up before on this sight or others, but I don't remember ever reading anything about this possibility.

Maybe in 2 or 3 years, I can say "see, I was right!"

Ryan

[Piers]

Yeah, I've often thought there is/will be more than the three.
I'm sure in the near future we will see some different expressions of genetics like in the palamino horse.
It should be fun.
Piers

[RandyRemington]

The numbers so far agree fairly well with leucistic being the homozygous version of a co-dominant mutation with the heterozygous version being lesser/mojave/phantom. However, the sample size on some of the crosses is pretty small.

The big test as to if leucistic is some sort of heterozygous combination will be when the first results of leucistic breedings are made public, hopefully in 05. If RDR breeds leucistic to a good number of normals and gets only lessers and phantoms (depending on the parentage of the particular leucistic) then we will have good evidence that the leucistic is a homozygous mutant condition and not a heterozygous combination like palomino.

It sounds to me like there may have actually already been at least four leucistic breedings but the results aren't public. I think Peter Kahl has produced at least once and perhaps more clutches from his original imported girl (perhaps an Ivory and not what we now call Leucistic). NERD posted a female leucistic on eggs this year. Vin Russo has pictures of a leucistic male breeding this year on his web site but didn't update it with results. And the imported male "Snoopy" supposedly bred at least once.

We'll eventually get the information to confirm how leucistic works but right now I'm betting they are homozygous and will produce all heterozygous mutant offspring (mojave, lesser, phantom, fireball, high yellow lemon, yellow belly, butter?) with a normal. It does look like yellow belly is probably not compatible with the other hets so it probably is right to separate Ivory from the Leucy group which may or may not all be compatible with each other.

[Scales Zoo]

Originally posted by RandyRemington
If RDR breeds leucistic to a good number of normals and gets only lessers and phantoms (depending on the parentage of the particular leucistic) then we will have good evidence that the leucistic is a homozygous mutant condition and not a heterozygous combination like palomino.


I'm not suggesting leucistic is heterozygous like palomino, I was thinking out loud and wondering if it is the homozygous recessive, like a cremelo (a horse that is white, sometimes with blue eyes, sometimes brown)

If the leucies bred to normals produce all normals, then this might be the case. That should also mean, that there is a homozygous dominant - either a less diluted color (like the chestnut - palomino horses), or possibly the homo's look like the hets (mojaves), and there are some super mojaves floating around that look like regular mojaves - or lessers or phantoms.

Also thinking out loud, maybe if the leucistics have proven to produce a bunch of normals, that is why no one has heard of any results yet.

Ryan

[varanus69]

my brain hurts now.............. way to much scientific stuff for me to follow........... guess i'm not that smart lol

[Artemis]

Amen to that Varanus... but I love the blue eyed leucies so much that I had to see if Scales had worked it all out. To me, palomino horse markings make me think of pied morphs, but I guess it doesnt genetically work out the same. Still in the first year of owning snakes period, so im not gonna try breeding anytime soon, but this is interesting stuff for sure.

The key to getting the crux of the arguement is this: (stolen from scales zoo):

Maybe it isn't the homozygous dominant (super) traits causing this, but the homozygous recessive traits (lack of any of the dominant traits - like the 1/4 normals one gets with pastel x pastel breedings)

I hope they figure it all out soon, cause I cant afford a BEL right now, but maybe before I die they will be cheaper than a cadillac finally!

Art

[RandyRemington]

maybe if the leucistics have proven to produce a bunch of normals, that is why no one has heard of any results yet

Maybe, but my guess is that they produced all subtle but visible hets and they don't want to make it easy for potential competitors to pick hets out of the tens of thousands of captive hatched brought in every year.

[NiagaraReptiles]

No offense guys, but I think you're expecting an awful lot for vigining projects. Ralph only first produced his line of Blue Eyed Leucy's in 2003, completely by accident involving multiple morphs, how much can you expect him to breed and hide from an '03?

Vin has produced clutches from his adult "white snake" and has offered all breeding information to the public. He had a bunch of babies in Daytona this past August and would gladly answer questions and show the differences between his hets and normals, though the differences in my opinion are very subtle (more so than the "traditional" yellow belly and/or goblin marker).

There are definately multiple strains of "leucistics"/white snakes out there now and they are being produced in a number of different ways. I don't think Black Eyes will be compatable with Blue Eyes and as for more details within each variety, time will tell.

JonK

PS - just for arguments sake, if you find an animal (out of the wild or unproven lineages) that somewhat represents and known marker/mutation, can you really label it as a known mutation until it is proven by captive breeding? This thought isn't only pertaining to the things being discussed in this thread.

[RandyRemington]

Ralph is the one big breeder that does post all his breeding results. I wouldn't mind more belly pics but basically his breeding record page is where I got my data to come up with the co-dominant theory. I've put together a spreadsheet with all of his leucistic related breedings starting in 2001.

I suspect Vin just hasn't updated his page since breeding started. I can't say much, I didn't update mine at all this year but then I didn't really have anything to sell. I'd love to make it to Daytona some year but it's not in the foreseeable future.

AFAIK Kahl and NERD aren't posting anything about the results of their leucy breedings and the Snoopy project is so darn secret that I don't even know who all owns him and for sure if he is really dead as rumored.

No, you couldn't sell a het leucy look-alike as a for sure het. However, now that there is a little info out on what they might look like I bet they most all get bred and where possible matched to a similar looking animal.

Some have said that Kahl's white import female might be an Ivory. I think he first bred her several years ago but nothing got out in public about what the babies might look like. It may well be that SnakeKeeper and Amir didn't even know when they started their yellow belly projects. I still don't think SnakeKeeper has posted belly pics of their het Ivories or confirmed that they are yellow bellies but once the rumor got out that they where buying up yellow bellies now anything remotely yellow belly like is getting bred. If Kahl had come out with detailed pictures of his white snakes babies years ago (and if they are indeed yellow bellies) there would be a lot more Ivories around now. Basically my point is that with up to 150,000 balls exported from Africa each year there should be plenty of subtle hets slip through and I think withholding information is one way of hoping most of them end up pets and not breeders to compete with the few in the know.

[RandyRemington]

There are definately multiple strains of "leucistics"/white snakes out there now and they are being produced in a number of different ways. I don't think Black Eyes will be compatable with Blue Eyes and as for more details within each variety, time will tell.

You are probably right about there being some incompatibility between lines. In hind sight I wonder if Davis' breeding his goblin (which he now indicates is a yellow belly) male to the phantom female that eventually produced his first leucistic was an early attempt to produce leucistics by combining suspected het lines based on non public information he had at the time. If Kahl's female is indeed an Ivory Davis might have suspected the goblin of being a leucistic het after seeing Kahl’s offspring. I don't know of any pre-existing breedings of leucistics to tip him off to the platty/mojave/phantom line hets but with all the secrets I don't doubt there could have been one. If goblin and phantom had been compatible hets for white snake Davis might have produced one in 01 and kicked off the public white snake craze that much earlier.