#horse patterns

[hor-wod-flir]

A guide to Horse Genetics in Horse Reality

(and real life)

@calaishorsereality asked for this but I thought others who wanna play the game or care about horses might find it interesting as well. I am gonna do this in two posts, first what do the genes mean for the horse you have, and then a second on how does the inheritance in foals work.

In horses and other animals you use letters for the different genes. Capital Letter means a horse has that gene, small letter means it does not have that gene.

Main Colors and Modifiers

These are the 3 main genes, that determine a horses color, the rest are dilutions or white patterns.

The horse shown in the picture has no extension gene, no agouti, and no grey, which means its a chestnut. The default horse color so to speak is chestnut, every other color needs at least one modifier present.

Extension

Extension is the gene name for black, if we assume a horse has no Agouti (aa) and no grey(gg), this is what your horse will look like based on the gene: ee = chestnut horse Ee = black horse EE = black horse

Agouti

Agouti is a very interesting gene because it needs Extension to show. I like to call Agouti red, which is wrong because even a horse with no Agouti is a chestnut aka red. If we assume a horse has no extenstion (ee) agouti will not show. aa = chestnut Aa = chestnut AA = chestnut If a horse has at least one copy of Extension (Ee), agouti makes the horses Bay. There are 3 distinctive shades of pure bay horses in HR: Bay, Wild Bay and Seal Brown. Please note that the genes that cause Wild Bay and Seal Brown in real life are not 100% known nor can they be tested for. In HR they also cannot be tested for but follow a predictable pattern of inheritance I will get into in the second section. In HR we use A+ for Wild Bay and At for Seal Brown. In real life telling Wild Bay and Bay apart is not easy in HR you can always tell it by the legs, the black on it is a lot lighter. For comparison, 3 Bay arabian stallions in game. Wild Bay, Bay and Seal Brown.

To recap how you can read the genes in game:

eeaa = Chestnut eeAa = Chestnut eeAA = Chestnut Eeaa = Black EEaa = Black EeAa = Bay EEAa = Bay EeAA = Bay EEAA = Bay

Grey

Grey is a fun little gene because it overpowers everything else, basically and 90% of every "white" horse you have seen is actually not white, its grey. Grey also is not an instant color, all grey horses are acutally born a non grey color and grey out over time. The genetics for it are rather easy, if there is just one G, that horse is grey. gg = non grey Gg = grey GG = grey In real life horses take years to turn fully grey, they get lighter with every coat change and run from "dappled" to "fleabitten" to fully grey. Since HR does not change a horses picture once its an adult, in order to reflect this your horse will randomly turn into one of the many grey coat variation a breed has. For Comparison Grey on PRE: Fully Dappled, partially dappled, fleabitten, fully grey.

Dilutions

Now things are gonna get more interesting.

Dilutions are a bit more "complicated" because they are not a base color but they influence the base color meaning every base color (Black, Red, Bay) will look differently with just one Dilution applied. And the Dilution can mix. Yeah. Yeah. Its a mess but its a fun mess.

Creampearl

Cream and Pearl both run on the same Allele meaning they are connected as heck. I do not have a biology or science background so I will focus more on just reading the gene testing rather than how they work. For Creampearl, if the horse does not have the gene you use n but if a horse has Cream we use CR. For pearl we use prl, if a horse has it. The small letter in this case indicate its a recessive gene, meaning if there is only one copy it doesn't show. Pearl either needs to copies of pearl or one pearl one cream. CreamPearl also increases with two copies. Meaning while a horse with one or two Extension will look the same, there is a drastic difference between a horse with one Cream or two copies of Cream. nn = no Cream Pearl Crn = Cream Horse CRCR = Cremello prln = just the base color, no dilution visible prlprl = Pearl CRprl= Cream and Pearl Black + Cream = Smoky Black (indistinguishable from black in HR) Bay + Cream = Buckskin Chestnut + Cream = Palomino

Dun

The Dun dilution comes in two variants, D and nd1. I will admit nd1 Is not one I am very familiar with and I have barely read anything about it in real life so I will focus mostly on D here. Dun is visible on all base coats, it gives the horse a lighter base color, plus the very distinctive primal markings on the legs and dorsal stripe. Non-dun1 causes primitive markings, without a dilution of the coat. The dorsal stripe is usually the most apparent marking. nd2/nd2 = no dun D/nd2 = dun D/D = dun nd1/nd2 = non-dun 1 nd1/nd1 = non-dun 1 D/nd1 = dun Most people have seen Dun in Fjord Horse since 95% of all Fjord Horses are Dun. But since I don't breed Fjords let me show it on Quarters.

Champagne and Silver

Champagne and Silver are not linked but since they work they same I am grouping them together. Both Dilutions show no difference if the horse has one or two copies. Silver does not show on chestnuts tho. nn = no Champagne CHn = Champagne CHCH = Champagne zz= no silver Zz = silver ZZ = silver

Mushroom

Mushroom is only present on Shetlands so I don't know much about it. Besides what the Wiki says. Mushroom is a recessive dilution, it does not show on black horses. n/n = no mushroom mu/n = no visible mushroom mu/mu = mushroom

Depending on which breed, lots of these Dilutions can be on one horse. I breed Quarters and they come in Cream, Pearl, Champange, Dun and Silver. The coat color changes to more unique colors the more dilutions a horse has.

White Patterns

As the name implies White Patterns are exactly that, white patterns. While the Base colors and Dilutions change more or less the whole color of a horse, White Patterns replace the normal hair color with white hairs in specific areas of a horse.

Frame / Overo

Frame, Overo or Overo Lethal White are white patches on the horses sides. The reason its called OLW is because having two copies of the gene will result in a deformed horse that won't live long after birth. In game the vet will "humanley" put it down right after birth. nn = no frame OWLn = Overo patches OWL/OWL = white all over + dead

Leopard/PATN1

These are another real complex one, while these are two different genes they always interact with each other so everyone groups them together. Back when I was still breeding Knabs I knew how it worked but now I gotta copy it from the wikipedia sorry.

Splash White 1-3

Splash White (SW) comes in 3 different genes, only the first type is in game yet, and is another type of white markings. Splash White mostly affects the face and the legs, when a horse has two copies the white can reach up to the belly and higher. nn= no splash white SW1n = Splash White SW1SW1 = increased splash white

Kit Genes

These are a fun bunch. These are a bunch of different pattern types that all lie on the same gene meaning a horse can only ever have two of them at once. Roan, Tobano and Sabiano 1 work the same, you need only one Copy to show the color, two copies are possible tho. n/n = no Kit Patterns RN/n= roan RN/RN= roan TO/n = Tobiano TO/TO = Tobiano TO/RN = Tobiano and Roan SB1/n = Sabiano 1 SB1/SB1 = increased Sabiano 1 (to be point of almost looking "white")

White Spotting

White spotting is a general name given to a large group of related white patterns. Currently, 34 different variations have been discovered in real life. At the moment, only W3, W10, W19, W20 and W21 have been implemented in-game. There are no W3/W3, W10/W10, W19/W19 horses in game because these comobs result in a miscarriage early in the pregnancy. Only W20/W20 can produce viable foals. White Spotting cannot be mixed together either.

These are all currently available in game, testable genes. There are a few more "hidden" aka non testable genes, like Flaxen, Pangare, Sooty and Rabicano and I will reblog this post with info on them tomorrow.

[sandrayln]

There's no "practically" about it, I am definitely asking you to nerd out about white coat patterns in horses. Also re: albinism in horses, as far as I understand albinism, there should be no reason why they *can't* be albino, just that they haven't mutated that set of genetic conditions. Same as peafowl, who also haven't. In sky cowboys verse, the pegasi evolved over a long time and through a cataclysm, so it's possible they just mutated the conditions themselves like they mutated wings. But Larn would have to answer that one for sure haha

lol Fair enough.

So... I can't get too deep into the genetics because a) not a genetic scientist and b) do not play one on Tumblr. lol Also, it makes my eyes cross to try and read those papers.

That said... I know the color genetics. So I can say... horse white patterns come in a number of groups, like so:

Appaloosa patterning

Classic roan

Grey

Tobiano

Frame white/lethal white overo

Splash

Dominant white and sabino

Untestable white

If I try and talk about all of those, this post is gonna be so ridiculously long, so let's leave off apps, roans, and greys right now, since they're not considered paint patterns.

Tobiano is relatively easy, and one of the more common patterns. If I understand the relevant genetics right, it's somewhat related to the piebald in mice, as is dominant white (but more on that in a sec). Imagine if you will that the white is draped across the horse's back and allowed to drape down, and you've got what Tobiano does in an average expression (a non-average expression ranges from a white tail or high white socks on the low end to extremely white on the high end). The white is rounded; the heads are typically the non-white color, though they can have facial markings to really complicate the issue. They may also have a "shield" of dark color on their chest and neck; skin under the white pattern is typically pink.

A horse can have one or two copies of the gene and they'll present pretty much the same. Because of the magic of genes sharing locations, if a horse has 2 copies of tobiano, they cannot be classic roan, sabino, or dominant white. They're all on the same gene, so you can only have 2 total... and if they're both tobiano, you're not getting anything else!

Frame overo, more properly known at this point as lethal white overo, puts white within the "frame" of the horse - in other words, it slaps big jagged white shapes across the horse's sides, not crossing over the center of the body. Skin under the white pattern is typically pink. It can also turn eyes blue, and it puts sharp, jagged edges on other white patterns if there are others in place. It can also hide pretty thoroughly. Ever seen a picture of a dark-coated horse with blue eyes? 50% chances that's a frame horse; if there's nothing to cause the white to pop, it can and will hide.

It's called lethal white because you can never, ever, ever have an adult horse with 2 copies of LWO. Horses born with 2 copies typically don't survive longer than 3 days, and are often humanely euthanized earlier; their intestines don't develop properly (something to do with the nerves, not sure I understand fully), and they just... it's not pretty. Breeders are heavily encouraged to test for LWO if there's any chance, because breeding 2 LWO horses runs a 25% risk of a dead foal.

Splash white is kind of the opposite of tobiano. Splash typically looks like someone picked up the horse and just dipped them in white paint: high white legs, a white belly spot, and big face white. They may also have blue eyes. Skin under the white pattern is typically pink. At its whitest, splash can produce an all- or nearly-all-white horse. There are I think four different versions of splash white, but in practice, there's a common one (sw-1) and three other versions that are limited to a small number of bloodlines within the Quarter Horse/Paint/Appaloosa/stock horse breeds.

A horse can have 2 copies of the splash genes - either two copies of one or one copy of two different ones. They think sw-3 might be lethal in 2 copies, though - they haven't found one yet, so it's just speculation that it causes abortions rather than the LWO issues. Splash horses are also slightly more likely to be deaf, particularly blue-eyed ones where the inner ear is missing pigment.

Dominant white and sabino are closely related in the patterning, which is why I grouped them together. Both tend to slap on irregular areas of white, often with a scattering of white hairs around the white (aka "roaning"). Skin under the white pattern is typically pink. Sabino is recessive; one copy will give irregular white, where two will give a near-white horse.

Dominant white, on the other hand, is wild. There are somewhere in the neighborhood of 35-40 discovered dominant white genes, typically in certain bloodlines. (10 of them are in Thoroughbreds, which makes me wonder what on earth is causing that...) All but one of them follow this same pattern as sabino, with ranges of expression from "a few little white blips" (like that Arabian above) up to completely white. Whether a horse can have 2 copies of a given dominant white gene varies by gene, and where they think it can't have 2 copies, usually the foal is aborted, not born.

And then there's W20, which... seems to just create the plain old normal white markings and enhance existing white patterns? And a significantly large number of breeds have it. It's such an anomaly, in both regards, but same gene group means it's a dominant white gene. It can definitely appear with 2 copies, and when it appears with a different W gene, it makes the markings much bigger and the horse much whiter.

And then there's the "other stuff." The white patterns that everyone knows are some kind of white thing, but nobody's figured out what yet.

That includes the draft-type sabino/white spotting, which probably is a sabino or dominant white pattern, but nobody's managed to track the gene yet. Not sure what a draft-type sabino looks like? Clydesdales. Also, Vanners (though Vanners are a melting pot of draft-type sabino, tobiano, splash, appaloosa patterns, and W20).

There's also rabicano, which puts white roaning across the ribs and flank and white at the top of the tail; it's more of a roan pattern than a pinto pattern, though, since it doesn't come with big blobs of color.

There’s machado, which... is either a paint gene that mutated in South America or something environmental down there, and no one’s sure which yet because it appears in several breeds.

Most of the other examples I can think of offhand have actually been identified as dominant white - the Thoroughbred Aidre Apache, for instance, was known to pass on what looked like a dominant white gene for years before they finally identified it.

There's also the mystery of what's controlling how white a given animal is. It's not necessarily the pattern - there are documented examples of apparently solid horses producing wildly marked foals, and vice versa. It seems like there are enhancers - like W20 - but there also seem to be suppressors, which I'm pretty sure my elder mare has some of those. They're just not genetically testable... yet.

Now, all that said... the original question was more about coat texture and strength, and in that aspect... there's not really a difference. There's some sun-related issues you can run into with the pink skin, because sunburn is a thing on pink skin, but that's really a thing with any pink equine skin, not just white patterns.