Horse Color Genetics Charts 2

Genetics Notation

Capital Letter = Dominant, expressed, trait is genetically "switched on"
Small letter= not expressed, trait is not "switched on"; or Recessive gene

I have listed below common genetic notation used by two of the most widely-accepted sources - Dr. Phil Sponenberg and Dr. Ann Bowling. In some cases, different notation is used, but if you look carefully, you will find that they are saying the same thing.

Remember that genetic notation is based on theories, which are used to explain Real World experiences. It is perfectly okay for one geneticist to use one system of genetic notation and another to use a different system, since it is all theoretical anyway. Only a few color genes have been definitively identified. These include red, black, Tobiano, and Frame (Overo).

"Locus" - meaning "place" can be a confusing term to the beginner. It refers to the placement of a certain factor on a DNA string. I prefer to use the term "genetic modifier," which is also used by Dr. Ann Bowling and the UC Davis biology dept.

COMMON GENETIC NOTATION White boxes denote notation used by Sponenberg, but not by Bowling and others
Gene	Name & What it does	Result
A	Agouti (Bay Modifier): Acts on "E" to restrict eumelanin to points; No effect on "e" or red	Bay
C	Non-dilute	Full Color
Ccr	Creme: Dilutes phaeomelanin markedly, eumelanin a little A single Ccr on RED = Palomino A single Ccr on BLACK = Smoky Black A single Ccr on BAY=Buckskin	Double Ccr dilutes the single creme colors even further: Double Ccr on Red = Cremello Double Ccr on Black = Smokey Cream Double Ccr on BAY = Perlino Photo: Andi Harmon; perlino mustang adopted by Greg Schultz
Ch	Champagne: A dilution gene that creates pumpkin-colored freckled skin, amber eyes, and unique bronze cast to hair coat	Champagne Champagne gene on Red =Gold Champagne on Bay = Amber Champagne on Black =Classic Champagne + Creme = Ivory
D	Dun dilution - dilutes both eumelanin and phaeomelanin	Dun on Red = Red Dun Dun on Bay = Dun, Zebra Dun, Bay Dun, Classic Dun Dun on Black = Grulla/o
d	Non-dilute	Full Color
Ed, E+	Dominant black, epistatic to A locus	Black
E	Dominant form of "Extension" locus; Allows either eumelanin (black pigment) or pheomelanin (red pigment) * (normal notation)	Black, unless other gene, such as A modifies Ranger from Coyote Lakes and his adopter, Karen
Ranger and Karen Blackwoode	Recessive form of "extension" locus; Allows Phaeomelanin (red pigment)only; epistatic to A locus	Red (chestnut, sorrel)
F	Red points on ee horses	Tostado or alazan
f	Flaxen points on ee horses (This is Sponenberg notation)	Ruano
Fr	photo: Ginny Freeman Frame Overo "Fr" is not the commonly accepted genetic symbol for frame overo. "O" is used in all scientific publications. Sponenberg uses the Fr symbol, but no one uses it. So a frame overo is Oo, and solids are oo.	Frame Overo Also: Overo Lethal White Syndrome
G	Grey - gradually covers and replaces any other color; eventually becomes white with dark skin	Dave Howe & Deserito Grey
Lp	Photo: Terry Crawford Leopard (NOT a single gene!)	Ajax, owned by Edona Miller Appaloosa Complex: leopard, snowflake, varnish roan, blanket, etc.
O	(Frame) Overo	Overo for registration purposes includes a variety of color patterns, but the genetic symbol, O, for Overo, refers to Frame Overo only.
P	Pangare ("Mealy") light golden areas over muzzle, eyes, elbow and flank	right photo by Judy Goulet “Belgian”Sorrel, Seal Brown, or "WILD DONKEY" Bay
Rb	Rabicano photo courtesy of arabianrun.com	Rabicano
Rn	Roan	Roan
Sb	Sabino	Sabino
Spl	photo by Marlene Maki Splashed White	Splash, Splashed White
Sty	Sooty/Smutty - black mixed into body coat	Sooty
To	Tobiano	Tobiano
W	White	Dominant White Pink skin, blue or brown eyes
Z	Karma, Cold Springs HMA Mustang adopted by Andi Harmon of Oregon Silver dapple - dilutes eumelanin only	Converts black to brown with white mane and tail

From "COAT COLOR GENETICS"
UC Davis, Dr. Ann Bowling

Genetic Formulas and Color Definitions

A=Agouti (a = no agouti)
Br = Brindle (br = no brindle)
C=Non-dilute, fully expressed color pigment
Ch = Champagne
Ccr=Cream/Creme
D=Dun (d= not dun)
E and e = the EXTENSION LOCUS, which determines whether or not Black pigment can be expressed
Dominant "E" allows either red or black (which in reality usually means a BLACK horse, unless other modifiers restrict the black; Recessive "e" allows only Red.
Fl = Flaxen mane & tail (fl = no flaxen mane & tail) works only on "ee" red based horses
Fr = Frame Overo (fr = non frame)
G=Gray (g = not grey)
Lp = Leopard (Appaloosa Complex; New research may prove this obsolete; the many Appaloosa color patterns may be caused by more than one gene)
lp = no leopard
P = Pangare (p = not pangare)
Rb = Rabicano (rb = not rabicano)
Rn = Roan (rn = not roan)
Sb = Sabino (sb = no sabino)
Spl = Splash (spl = no splash)
-Sty = Sooty/Smutty (-sty = no sootiness)
To=Tobiano (to = not tobiano)
W=Dominant White (w = not dominant white)
Z = Silver Dapples (z=no silver)

Sponenberg uses a more complex and slightly different notation:

A = restricts black to points (bay)
a=uniform brown/black over entire body
B=Black
b=brown
C=non-dilute, fully expressed
cr=cremello dilution
D=dun dilution; D dilutes both black and red base colors
d=non-dilute, or no dun
Ed=dominant Black
E=allows black color on points
e=red
F=red points on ee horses
f=flaxen points on ee horses
P=Pangare
p=non-pangare
Sty=Smutty/Sooty= black mixed into body coat
sty=clear, non-sooty
Z=Silver Dapples: dilutes black to silver dapples; dilutes bay and brown to mimic sorrel; dilutes buckskin to appear near-palomino
z=no Z dilution
G=grey
g=no grey
Rn=Roan
rn=non-roan
T=Tobiano (pinto spotting)
t=non-Tobiano, not spotted
O=not spotted
o=Overo spotted
Sb=Sabino spotting
sb=non-Sabino
Spl=non-splashed White
spl=Splashed White
Rb=Rabicano
rb=non-Rabicano
Lp=Leopard (appaloosa complex)
lp=no leopard complex
W=White
w=not white

VIDEOS OF INTEREST TO MUSTANG & BURRO ADOPTERS:

Kitty Lauman:
From Wild to Willing: Using the Bamboo Pole to Gentle Mustangs
More from Lauman Training available now!

Lesley Neuman:
The First Touch
Gentling Your Mustang
$45.00

Capital Letter = Dominant, expressed, trait is genetically "switched on"
Small letter= not expressed, trait is not "switched on"; or Recessive gene

From "COAT COLOR GENETICS"
UC Davis, Dr. Ann Bowling

Genetic Formulas and Color Definitions

A=Agouti (a = no agouti)

C=Non-dilute, fully expressed color pigment

Ccr=Cream/Creme

D=Dun (d= not dun)

E and e = the EXTENSION LOCUS, which determines whether or not Black pigment can be expressed
Dominant "E" allows either red or black (which in reality usually means a BLACK horse, unless other modifiers restrict the black; Recessive "e" allows only Red.

Fr = Frame Overo (fr = non frame)

G=Gray (g = not grey)

To=Tobiano (to = not tobiano)

W=Dominant White (w = not dominant white)

VIDEOS OF INTEREST TO MUSTANG & BURRO ADOPTERS:Kitty Lauman: From Wild to Willing: Using the Bamboo Pole to Gentle MustangsMore from Lauman Training available now!

Lesley Neuman:The First TouchGentling Your Mustang$45.00

Capital Letter = Dominant, expressed, trait is genetically "switched on"Small letter= not expressed, trait is not "switched on"; or Recessive gene

From "COAT COLOR GENETICS" UC Davis, Dr. Ann Bowling

Genetic Formulas and Color Definitions

A=Agouti (a = no agouti)

C=Non-dilute, fully expressed color pigment

Ccr=Cream/Creme

D=Dun (d= not dun)

E and e = the EXTENSION LOCUS, which determines whether or not Black pigment can be expressedDominant "E" allows either red or black (which in reality usually means a BLACK horse, unless other modifiers restrict the black; Recessive "e" allows only Red.

Fr = Frame Overo (fr = non frame)

G=Gray (g = not grey)

To=Tobiano (to = not tobiano)

W=Dominant White (w = not dominant white)

VIDEOS OF INTEREST TO MUSTANG & BURRO ADOPTERS:

Kitty Lauman:
From Wild to Willing: Using the Bamboo Pole to Gentle Mustangs
More from Lauman Training available now!

Lesley Neuman:
The First Touch
Gentling Your Mustang
$45.00

Capital Letter = Dominant, expressed, trait is genetically "switched on"
Small letter= not expressed, trait is not "switched on"; or Recessive gene

From "COAT COLOR GENETICS"
UC Davis, Dr. Ann Bowling

E and e = the EXTENSION LOCUS, which determines whether or not Black pigment can be expressed
Dominant "E" allows either red or black (which in reality usually means a BLACK horse, unless other modifiers restrict the black; Recessive "e" allows only Red.