Genetics Help

_ means either a dominant allele or a recessive allele can be entered and there will be no difference (for example, E_ can be either EE or Ee and will still be black!

Black dominant, chestnut recessive.

♦ Black: E_
♦ Chestnut: ee

Works on a black base. Does not show on chestnut, so it's hidden.

♦ Bay: A_ (least dominant)
♦ Seal Brown/Bay: A^t_
♦ Wild Bay: A⁺_ (most dominant)
♦ No Bay: aa

♦ Examples:
Chestnut (ee/A^tA)
Chestnut (ee/Aa)
Wild Bay (Ee/A⁺A)

Similar to the agouti genes, dilution genes act on the base colors (including bay). They change the base color, and give you a different color based on which base they are working on! They can also compound on each other, at which point things get a bit complicated (but fun!). Incomplete dominance means the gene acts differently with one dilute present than it does with two. "n" here denounces no copy.

♦ Champagne: Ch_ (dominant)
♦ Gold Champagne: Ch_/ee/aa
♦ Classic Champagne: Ch_/E_/aa
♦ Sable Champagne: Ch_/E_/A^t_
♦ Amber Champagne: Ch_/E_/A_

♦ Cream: Cr_ (incomplete dominance)
♦ Palomino: nCr/ee
♦ Cremello: CrCr/ee
♦ Smokey Black: nCr/E_/aa
♦ Smokey Cream: CrCr/E_/aa
♦ Smokey Seal Brown: nCr/E_/A^t_
♦ Seal Brown Cream: CrCr/E_/A^t_
♦ Buckskin: nCr/E_/A_
♦ Perlino: CrCr/E_/A_

♦ Dun: D_ (dominant)
♦ Red Dun: D_/ee
♦ Grullo: D_/E_/aa
♦ Brown Dun: D_/E_/A^t_
♦ Dun (Classic): D_/E_/A_

Now, this one gets a bit complicated, so bear with me! It also acts in conjunction with Cream. There is still a lot of research that needs to be done on the pearl gene.

♦ Pearl: PrlPrl (recessive)
♦ No effect: nPrl
♦ Apricot: PrlPrl/ee
♦ Pearl (Classic): PrlPrl/E_/aa
♦ Pearl (Lighter?): PrlPrl/E_/A_
♦ Pseudo Cremello: PrlPrl/nCr/ee
♦ Pseudo Perlino: PrlPrl/nCr/E_/A_

♦ Silver: Z_ (Dominant, works on black)
♦ No effect: Z_/ee
♦ Silver Dapple: Z_/E_/aa
♦ Brown Silver Dapple: Z_/E_/A^t_
♦ Bay Silver Dapple: Z_/E_/A_

I don't know if this next one is technically a dilution, but probably?

♦ Flaxen: ff (recessive, acts on chestnut)
♦ No effect: ff/E_
♦ Flaxen Chestnut: ff/ee

Sooty isn't incredibly well understood, but we're going to treat it as a simple dominant gene with variable expression.

♦ Sooty: Sty_ (dominant)

Dominant white is homozygous lethal in some varieties, so we're going to run with that. I know there's more exact genotyping for dominant white now, but this is how we're going to use it!

♦ Dominant White: W_ (dominant, homozygous lethal)

♦ Frame Overo: Oo (incomplete dominance)
♦ Lethal White Syndrome: OO (lethal)

♦ Splash White: Spl_ (incomplete dominance)
♦ Minimal Splash: nSpl
♦ Classic Splash: SplSpl

♦ Sabino: Sb_
♦ Minimal/Classic Sabino: nSb
♦ Maximum Sabino: SbSb

♦ Tobiano: T_ (dominant)

♦ Tovero: T_/Oo

Appaloosa genetics are some of the most complicated that breeders have to work with - there's just so much that goes into them, including sex link! We're going to go a bit simpler than the most recent research and not link it to sex.

♦ Leopard Complex/Varnish Roan: Lp_ (incomplete) - required for any other pattern to show!
♦ Varnish Roan (less white): nLp
♦ Varnish Roan (more white): LpLp

♦ PATN1: PATN1_ (dominant, also dominant to PATN2)
♦ Leopard Appaloosa: PATN1_/nLp
♦ Fewspot Appaloosa: PATN1_/LpLp

♦ PATN2: PATN2_ (dominant)
♦ Blanket Appaloosa: PATN2_/nLp
♦ Snowcap Appaloosa: PATN2_/LpLp

Rabicano is poorly understood overall, but this is how we're going to do it.

♦ Rabicano: Rb_ (dominant)

♦ Roan: Rn_ (dominant)

♦ Pangare: P_ (incomplete)
♦ Tan Points: Pp (mild pangare)
♦ White Points: PP (lighter pangare coloring, ie Belgians)

♦ Grey: G_ (dominant)

These markings/colors are not understood and the method of inheritance is not typical. If you want to use these colors or pass them down to a foal, they have to be bought from the store.

♦ Brindle (store item)
♦ Reverse brinde (store item)
♦ Chimera (store item)

Since donkeys have less genes overall to look at, I'm grouping them here. Please note that as far as I can tell, donkey genetics are fairly poorly understood, so I took some liberties as far as dominance. If you find an error, please link me to a website with information to fix it!

Base Color
♦ Black: E_ (dominant)
♦ Red: ee
♦ Bay: A_

♦ Ivory: ii (recessive)
♦ No effect: Ii or II
♦ Slightly darker on black base, average on red base, palest on dun base

♦ Dun: D_ (dominant, incredibly common!)
♦ Grey Dun: D_/E_/aa
♦ Rose/Red Dun: D_/ee
♦ Bay Dun: D_/E_/A_

♦ Pangare: P_ (incomplete, very rare not to have it. Most are PP)

♦ Roan: R_ (dominant)
♦ Frosting: F_ (similar to grey in that it becomes progressively more white, but can be patchy)

Spotting appears to only occur on black bases, so red may be a carrier. Blue eyes are unusual but possible.

♦ Spotting: nSp
♦ Lethal: SpSp

♦ Star: St_ (We're going to call it dominant. Not much is known about it. Causes no other markings.)

♦ Dominant White: W_ (homozygous lethal)

Please note: Genetics are generally listed in the order shown. For example, a buckskin tobiano should be listed Ee/AA/nCr/Tt, but not AA/nCr/Ee/Tt.

Horse Color Genetics Tool