Grey Horse Modifier

The greying gene is found in all breeds of horses and has the ability to mask all other colors, including pinto and appaloosa white patterns.

Grey horses are unique because they are born dark, with either black or chestnutbase and slowly “grey out” with every shedding. All horses affected by the grey modifier grey out, no matter what color they are born.

About the Grey Modifier

Dominant gene
Modifier that depigmentates colored hairs as the horse ages
Skin may also depigmentate which causes mottling
Greying varies between horses and breeds
First signs of greying are usually around the eyes
All gray horses grey out no matter what color they began

Different Greying Stages

Every grey horse will go through all of the below stages at some point in their life. Greying varies between horses and breeds.

Steel / Iron Greying Stage

First stage of greying process
Face tends to lighten first
Can have a bluish tint
Often mistaken for grullo

Dapple Greying Stage

Second stage of greying process
Most commonly expect when they think of grey horses
Occurs during ages of 4-12 & vary by speed of greying and age

White Greying Stage

The third stage of the greying process
Horses who have finished greying out
All pigment in hair is gone

Fleabitten Greying Stage

Image from Montanabw

Last stage of the greying process
Horses have small red or black spots all over their body hairs
Sometimes they start as they horse begins to grey out and others sprout up after greying process is complete

Rose Grey

Horses that have a bay or chestnut base coat
As horses grey out they have a rosy tint to their coat

Bay Color Modifier

Perhaps one of the most well known horse colors, the bay comes in a variety of different shades and can be identified by their black points (mane, tail and legs).

A bay horse is an animal with a black base affected by the Agouti gene which controls the distribution of black hair to points and topline. This gene only affects a black base because chestnut hides the Agouti gene.

Bay Modifier

A dominant color
Common in all breeds
Red body ranging from light to dark with black points
Wild bay is a rare subtype with black legs that only extend up to pastern or fetlock

Different Bay Shades

There are a variety of different bay colors and they fall under these general categories.

Black Bay

Image from Rror

Mahagony Bay

Image from Shagya France

Blood Bay

Standard Bay

Image from Reynaldo

Light Bay

Bay Dilutions

A bay base can be affected by all of the dilution genes & display a brilliant rainbow of colors as a result. Here are a few examples.

Bay or Zebra Dun

Bay horse with a dun modifying gene

Image from Podargus

Buckskin

Bay horse with a cream modifying gene

Image from Rozpravka

Perlino

Bay horse with a double dose of the cream modifying gene

Image from Arsdelicata

Amber Champagne

Bay horse with a champagne modifying gene

Image from Kersti_Nebelsiek

Silver Bay

Bay horse with a silver modifying gene

Image from Philipendula

Bay Modifications

The bay color itself is a modifying gene, however the color can be affected by two of the other modifications as well (mealy & sooty). Here are examples.

Mealy / Pangare

Bay horse with a mealy / pangare modifying gene

Image from me’nthedogs

Sooty / Smutty

Bay horse with a sooty / smutty modifying gene

Image from selenas_stock

White Patterns

Bay animals can be affected by all white patterns and the bay coloring actually creates more colorful spotted animals (think tri-colored pintos).

Appaloosa

Bay horse with a appaloosa white pattern

Image from equessaquagrl

Skewbald Pinto / Paint

Bay horse with a paint / pinto white pattern

Image from Borsi112

Bay Roan

Bay horse with a roan white pattern

Mealy / Pangare Modifier

Image from GerardM

This color modifier is common in all breeds is expressed by a lightening of the animals soft spots, generally the muzzle, belly, flank, elbow and eyes. This gene is also often found in mules and burros, and easily identified by a characteristic lightened muzzle.

Mealy Modifier

The picture below is a fine comparison of two similar colored horses, one with the Pangare gene and one without.

Mealy vs. Non-Mealy

Image from Deivis

Mealy Colors

The mealy gene can be displayed on all of the base colors and the bay modifier. Here are some obvious examples.

Chestnut Mealy

Mealy gene displayed on a chestnut base

Image from White Horse Productions

Black Mealy

Mealy gene displayed on a black base

Image from Apple Ridge Mountain Horses

Bay Mealy

Mealy gene displayed on a bay horse

Image from me’nthedogs

Sooty / Smutty Color Modifier

Image from Tocekas

Thought to be a form of natural camouflage, the sooty or smutty gene causes black hairs to grow mixed into the body coat (generally along the topline & points). This often results in dappling and in rarer cases brindle striping.

Sooty / Smutty Modifier

Can be a seasonal effect as some buckskins who display darker striping and shading along their topline during certain times of the year. Experts don’t know if this is related to the primitive striping found in duns, although buckskins who display it can be mistakenly identified as dun.

Darkens color in specific areas
Can cause dapples
Can cause individual black hairs
Generally causes a darker shade on the topline
Can darken uniformly
Also called countershading or coloring

Smutty Colors

This coloring can be found on both black & chestnut bases (that includes bays). Although darkening of the coat only has a visible affect on variations of bay & chestnut animals.

Basic Genetics

The presence of black hairs on a chestnut based animal poses a contradiction, as the ‘ee’ gene blocks production of black hairs. It is thought that the sooty gene cancels out the black pigment blocking properties of ‘ee’ animals. This is largely believed because even palominos (also affected by a creme dilution gene) can also grow black colored hairs that are not diluted by the cream gene.

Although the cause of this coloring and how it’s passed on genetically is unknown it’s passed on readily enough to be dominant to some degree.

Sooty Bay

Sooty gene displayed on a bay horse

Image from Martin_Bahmann

Sooty Palomino (Chestnut)

Sooty gene displayed on a chestnut base (with a creme modifier)

Image from Just chaos

Sooty Buckskin (Chestnut)

Sooty gene displayed on a bay horse (with a creme modifier)

Image from Rozpravka

Flaxen Color Modifier

Image from Mihai Bojin

The flaxen modifier only affects mane and tail color in chestnut based horses. This gene displays in a white to cream colored mane and tail with a reddish body coat, and does not always affect the mane and tail to the same degree.