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.













