A free to use illustrated guide to horse coats.
*these genetics are modified to common use in online adoptables and may not be true to real life genetic testing*
Page One - Base Coats and Basic Markings
Black..............................................................................................................................................
-Base Coat
Notable Gene: Extension [E]
Variations: True/Solid, Fading
Description: A solid base, black in colour. Rarely a true
black, more commonly faded.
Geno: E_ aa
Agouti [a] is always lowercase.
Bay
-Base Coat
Notable Gene: Agouti [A]
Variations: Standard, Blood, Mahogany, Copper, Gold, Dark
Description: Brown in colour, with black points and mane.
Geno: E_ AA // E_ Aa
Agouti [a] cannot be wild [A+].
Wild Bay
-Base Coat
Notable Gene: Agouti [A+]
Variations: N/A
Description: Bay with minimal black points.
Geno: E_ A+A+ // E_ A+A // E_ A+a
Seal Brown
-Base Coat
Notable Gene: Agouti [At]
Variations: N/A
Description: (Dark) brown with extensive black. Not bay!
Geno: E_ AtAt // E_ Ata
Below Wild [A+] and Bay [A] in dominance.
Chestnut
-Base Coat
Notable Gene: none
Variations: Standard, Cherry, Sorrel, Golden, Liver, Black
Description: A solid base, usually reddish or orange,
sometimes darker.
Geno: ee __ // ee aa
Can have agouti genes, but won't present.
-Base Coat
Notable Gene: Extension [E]
Variations: True/Solid, Fading
Description: A solid base, black in colour. Rarely a true
black, more commonly faded.
Geno: E_ aa
Agouti [a] is always lowercase.
Bay
-Base Coat
Notable Gene: Agouti [A]
Variations: Standard, Blood, Mahogany, Copper, Gold, Dark
Description: Brown in colour, with black points and mane.
Geno: E_ AA // E_ Aa
Agouti [a] cannot be wild [A+].
Wild Bay
-Base Coat
Notable Gene: Agouti [A+]
Variations: N/A
Description: Bay with minimal black points.
Geno: E_ A+A+ // E_ A+A // E_ A+a
Seal Brown
-Base Coat
Notable Gene: Agouti [At]
Variations: N/A
Description: (Dark) brown with extensive black. Not bay!
Geno: E_ AtAt // E_ Ata
Below Wild [A+] and Bay [A] in dominance.
Chestnut
-Base Coat
Notable Gene: none
Variations: Standard, Cherry, Sorrel, Golden, Liver, Black
Description: A solid base, usually reddish or orange,
sometimes darker.
Geno: ee __ // ee aa
Can have agouti genes, but won't present.
Tobiano
-Marking
Notable Gene: Tobiano [To][T]
Variations: Minimal, Standard, Extensive, Maximum
Description: White markings that usually cover the legs and
touch the back.
Geno: __ ToTo // __ nTo
Part of KIT gene. RnTo | SbTo | WTo
Overo
-Marking
Notable Gene: Overo [O]
Variations: Minimal, Standard, Extensive, Maximum, Framed
No such thing as reverse frame!
Description: White markings that do not usually touch the back.
Cannot be two dominant genes due to lethal white syndrome.
Geno: __ Oo
Tovero
-Marking Combination
Notable Genes: Tobiano [To][T] , Overo [O]
Variations: Minimal, Standard, Extensive, Maximum
Description: White markings. Tobiano and Overo present.
Geno: __ To_ Oo
Splash
-Marking
Notable Gene: Splash [SPL]
Variations: Minimal, Standard, Extensive, Maximum
No such thing as reverse splash!
Description: White marking along bottom of horse. White
face usually present. Part of 'overo family.'
Geno: __ SPLSPL // ___ SPLspl
Tovero
-Marking Combination
Notable Gene: Tobiano [To][T] , Splash [SPL]
Variations: Minimal, Standard, Extensive, Maximum
Description: White markings. Tobiano and Splash present.
Geno: __ To_ SPL_
-Marking
Notable Gene: Tobiano [To][T]
Variations: Minimal, Standard, Extensive, Maximum
Description: White markings that usually cover the legs and
touch the back.
Geno: __ ToTo // __ nTo
Part of KIT gene. RnTo | SbTo | WTo
Overo
-Marking
Notable Gene: Overo [O]
Variations: Minimal, Standard, Extensive, Maximum, Framed
No such thing as reverse frame!
Description: White markings that do not usually touch the back.
Cannot be two dominant genes due to lethal white syndrome.
Geno: __ Oo
Tovero
-Marking Combination
Notable Genes: Tobiano [To][T] , Overo [O]
Variations: Minimal, Standard, Extensive, Maximum
Description: White markings. Tobiano and Overo present.
Geno: __ To_ Oo
Splash
-Marking
Notable Gene: Splash [SPL]
Variations: Minimal, Standard, Extensive, Maximum
No such thing as reverse splash!
Description: White marking along bottom of horse. White
face usually present. Part of 'overo family.'
Geno: __ SPLSPL // ___ SPLspl
Tovero
-Marking Combination
Notable Gene: Tobiano [To][T] , Splash [SPL]
Variations: Minimal, Standard, Extensive, Maximum
Description: White markings. Tobiano and Splash present.
Geno: __ To_ SPL_