Confused about Appaloosa!

[Stick]

This is the first time that I've shown my face in the forum, so I'm a little nervous! But, I just can't figure this one out. I'm running an Appaloosa experiment on my farm, and I really thought I'd gotten the hang of how the LP basics works, but this latest birth says that maybe I don't.

First, I got a snowflake-showing shetland stallion from the AC, figuring that will guarantee that he carries the LP "master switch," and I'll use him to test AC mares for PATN genes. That's what I did for a while--breeding mares to him and rehoming them if they didn't throw appaloosa foals after two tries. It seemed to be working how I would expect.

But then, on a whim, I bred him to a snowflake-showing tarpan female from the AC, and figured I'd either get a PATN-less foal, or one with more snowflakes... but, instead, I got this:

Nickel


Where did that blanket come from? Were one of her parents not LP-carriers without patterns like I thought they were?? I'm wondering now if my whole experiment is inaccurate now.

So, this is a "what color is my horse?" post for both this filly, and her AC parents:

Sprinkles

Alloy


Thanks in advance! I want to learn how this works.

[Kayaine]

Ping

So when the app pattern first came out, I bred them. A lot.

The one thing I can tell you about them is they will always surprise you. Sometimes, you'll get a seemingly spotless horse that varnishes. Sometimes you'll go from spots to blankets.

The best way I can think to explain what happened is this:

Any horse that varnishes carries some form of the "on" switch or LP. Horses have a chance of carrying PATN as well even if they don't have the LP. I've found that thinking of PATN like a glass that you can add water to helps me. I think of your stud as carrying very little water in his glass. Sometimes, he'll pass some portion of water on to his foals glass, and like everything else, how much he passes will vary. The same thing with the mare. So in the end, your foal may have more water in his glass (or snowflakes in this case) then either of his parents, more than 1 but less than the other, or less than both, or even, none at all. I can't tell you an absolute for why snowflakes can mysteriously turn into blankets though.

It always seemed to happen to me with very spotted horses. I usually thought of it as having enough water in the glass that (enough of the PATN gene) it overflowed and splattered a blanket everywhere. So it happens sometimes, but not others. And because it's difficult to tell in any given pair that produces snowflakes only how much PATN they can truly pass on before a blanket happens, it's hard to guess what you'll get. Usually, you should just get more snowflakes, but sometimes, you'll splash over and get a blanket.

Hope this helps!

[Stick]

Hoo boy! That was confusing, but I think I understand--at least a little bit.

Am I right in understanding that those AC parents weren't totally PATN-less, then? Basically, the snowflakes aren't an expression of master-switch-without-pattern like I thought they were, but they are actually a sign that they have (or maybe carry?) a very mild PATN gene? Is that more or less right?

And thank you for helping!

[Stick]

ping!

Oh, actually, I did have one more question! The other thing I was confused about with that filly was wondering why her blanket didn't have that small-spot, "fuzzy" edge to it. From what I'd understood about LP/Lp vs LP/LP was that heterozygous markings have the normal appy edge to them, and the homozygous ones have the fuzzy edges with small spots.

This filly, for example, is the daughter of a second-gen blanket horses and one of those snowflake AC stallions I have. I'd expected this foal to inherit one LP and a PATN from her blanketed parent, and another copy of LP from the snowflake one, and she did turn out with that result:

Misty


But the filly that I'd first mentioned doesn't have those fuzzy edges, even though she has two AC snowflake parents. The only thing I could think of is that maybe the LP horses from the AC can actually only be heterozygous for LP? And, if that's the case, maybe I should be testing them with AC mares more than twice before I assume the mares don't have PATN genes? Because, if the offspring aren't showing appaloosa, maybe it's actually the snowflake-parent's fault, because they're only heterozygous for LP??

Phew... I feel like I'm rambling, but I hope this makes sense. Thanks again in advance to anyone who wants to try helping me out with this. :'D

[BlackOak2]

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To continue with what Kayaine was saying (really good explanation by the way), it depends on how the genes react with one another and the way they're input. The original post that has quite a bit of information that I found helpful is found here, there is also this one, if you haven't already seen it. That second one is the original announcement that offers an in depth introduction of what a horse can have without saying exactly what they have or what breed will carry exactly what.

Snowflake is controlled by two genes and (mostly by visual assumption) seems to be an incomplete dominant (which generally means that as long as the horse has at least one Lp gene to turn it on, if the horse carries a snowflake gene, it will always develop some sort of snowflakes. But... since it's controlled by two genes... then what happens if a foal is born with both genes? If we are to assume that some of the snowflake horses we see from the AC, carry just one of these genes, then as long as it passes this single gene on (a 25% chance, by the way), then as long as the foal also inherits the Lp gene (from the sire, another at least 25% and no more than 50% chance if the mare shows no patterns at all), you will get a snowflake foal, but that only proves that the sire is passing on those genes, not that the mare is.
But with only a 25% (assuming your sire that shows color, carries only one of the Lp and one of the snowflake) chance of passing those colors, offering only two foals with an unknown carrier mare isn't really fair to the mare. What you would want, is to guarantee that one parent (either the mare or the sire) has two copies of both, that guarantees that the foal will offer some sort of color. But here's the problem. What happens when you have two Lp genes? And what happens when you have two snowflake genes?

Like Kayaine said, I also have the theory that if you produce a foal carrying both snowflake genes, it will produce a spotted blanket with the snowflakes. But... that could also be an expression of a specific allele and not the expression of the gene itself (an allele is a part of the gene).
So... perhaps that mare carries the spotted blanket allele expression on one of her genes that cannot show itself unless it has both snowflake genes; this would make the specific allele recessive and could only reveal itself in descendants if the partner also showed the blanket and pattern gene.

But... that's assuming a lot of information I haven't yet figured out.

The first assumptions you can make with appaloosa patterning is that any horse that shows either snowflakes or spotting, definitely carries a master switch and definitely carries some sort of patterning genes. You can also make this assumption if you see any non-pattern horses that carry varnish (all of our horses that carry the master switch will also carry the varnish).
So maybe that would have been a better place to start. Find a horse that carries varnish but no snowflakes and no spots (although snowflakes are notorious sometimes for finding, they can hide under manes, in white varnished areas and though I can only guess, but also on the other side of the horse, including behind legs, stomach and under tails). That would have offered perhaps a more in depth understanding of what the horses being bred to, carried.

Check out those links too, they helped me and I do still refer back to them from time to time when I forget something (actually I have them bookmarked).

It is a long process experiment you have going on, good luck and have fun!

[Kayaine]

ping

I think it is moderately safe to say that LP carrying horses from the AC are probably mostly if not always heterozygous. All the blanket patterned AC horses are heterozygous, so I would assume the snowflake patterned ones are too.

[Stick]

Dang... I'll have to read over that explanation more carefully later (I am currently getting ready to fly across the country tomorrow), but I think I'm starting to hone in on the things that I'd had incorrect understandings about. I had actually read both of those threads (thank you for linking them, though!) and even have them both linked in my farm description so I can find them easier, lol. However, looking at them again and comparing to what you're all explaining, I think I'm starting to see where I got mixed up on a couple of things I'd read.

I think I was putting snowflake and varnish on the same tier of being things that show up with LP and don't need a PATN gene. So, snowflakes having anything to do with blankets at all didn't make sense to me. Now, I'm starting to think of snowflakes being a little more complicated than that. Also, the thought of things like blankets (whether they are expressions of PATN, or double snowflake, or something else) possibly being recessive is something I hadn't considered before. I'd also assumed that the Shetlands and Tarpans that serve as the LP-carriers would be homozygous, but I have no idea where I would have gotten that idea from, lol.

So, with all that, I think I'll be giving my mares more chances to throw marked foals, and I'll start doing more tests to see what happens when you cross two snowflake-only horses. The experiments aren't as clean as I'd like anymore, but I think I'll still end up learning something from it! I've already found more evidence that Forest Horses carry the big spots, Caspians have really interesting "crawling" shapes to their white areas, and Arabians carry dense spots. No new discoveries yet, but I'm looking forward to possibly stumbling upon something eventually. :}

[BlackOak2]

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The more we have that work on these things, the more opportunity we have to establish and prove what offers what. To give you a little more insight (I do have some additional notes if you want them, or if you want to test them yourself and be surprised, that's fine too)...Forest horses do offer the big spots, caspians do offer white spreading genes and arabians offer a closer density to the spots.

But not everything about them has been fully researched (or in some cases, perhaps not researched at all, since nobody has authored anything about certain traits), so any additional information, even if it's already known (because it confirms what has been found previously), is always helpful.
Especially if you choose to focus on one thing.

And of course, have fun!

[Stick]

...

Just replying now because I've been out of the state for my sister's wedding this past week. Just now returning to the internet!

Thanks for the reply... and I am super curious as to what notes you've been gathering yourself, even though I'm also stoked to start discovering things for myself. The only way to message one another privately is to have an upgraded account, right?

[BlackOak2]

...

Just replying now because I've been out of the state for my sister's wedding this past week. Just now returning to the internet!

Thanks for the reply... and I am super curious as to what notes you've been gathering yourself, even though I'm also stoked to start discovering things for myself. The only way to message one another privately is to have an upgraded account, right?

Yes, only upgraded accounts have the ability to access private messaging. There is chat and private messaging while in chat, but that (obviously) requires people to be on at the same time.