WEBSITE WAS UPDATED: 2/17/2024
GOAT COLOR GENETICS
Welcome to the vibrant world of goat color genetics, where curiosity meets color!
Whether you're just starting your journey into the exciting realm of goat genetics or you're an experienced enthusiast looking to deepen your understanding, you've landed in the right place. This page is designed with both beginners and seasoned goat enthusiasts in mind, breaking down the intricacies of color genetics into a friendly and digestible format.
We'll guide you through the basics, unraveling the mysteries of coat colors, patterns, and the fascinating genetic combinations that make each goat uniquely beautiful. Whether you're here to learn, share, or simply marvel at the kaleidoscope of goat colors, we're thrilled to have you on board.
Let's explore the world of goat color genetics together – where every stripe, spot, and shade has a story to tell!
Are you brand new to genetics?
If you want to learn the basics...
Attention: Boer Goat Enthusiasts!
If you want to only focus on boer genetics...
AGOUTI LOCUS
The Agouti Locus is a hot topic in the goat community because it plays a major role in the wide variety of color patterns we see in goats. This locus is the base layer of paint. The job of this locus is to decide where the eumelanin (black) and pheomelanin (tan) are distributed on the goat.
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The most dominant pattern is A(wt) aka Gold , and it can conceal any other Agouti pattern.
The least dominant pattern is A(a) aka No Pattern, and it can be hidden by any other Agouti pattern.
Every other Agouti pattern is co-dominant. More about this in the Combination Patterns section!
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Keep in mind that every single goat, carries two patterns (alleles) on each locus.
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Below are the most common Agouti patterns in the USA:
 Gold - A(wt) |  Caramel - A(c) |  Blackbelly - A(bb) |
|---|---|---|
 Bezoar - A(+) |  Buckskin - A(sc) |  Peacock - A(p) |
 Swiss - A(sm) |  Black and Tan - A(bt) |  Red Cheek - A(rc) |
 No Pattern - A(a) |
EXTENSION LOCUS
For most goat breeds, discussions surrounding the Extension Locus are relatively limited. With the exception of Boer and Angora goats, the presence of the dominant black allele is quite rare. Similarly, outside of Nigerian Dwarfs, the occurrence of the recessive red allele is very uncommon.
Now, we know the Agouti Locus acts like the base layer of paint.
The Extension Locus acts like the top coat.
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A goat's coat color is determined by one of three options, in order of dominance:
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Dominant Black - E(D):
​One copy of this allele covers the entire animal in eumelanin, resulting in a black coat.
Think of this like a opaque black top coat that covers anything underneath.
Wild Type - E(+):
The wild type allele allows the expression of the underlying pattern from the Agouti Locus.
Imagine this allele as a translucent, clear top coat that shows the pattern beneath.
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Recessive Red - E(e):
Two copies of this allele creates an inability to produce eumelanin, resulting in a solid pheomelanin (tan) coat.
Picture this allele as an opaque red top coat that hides anything underneath.
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Below are illustrations of each pattern:
Dominant Black - E(D) |  Wild Type - E(+) | Recessive Red - E(e) |
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BROWN LOCUS
The Brown Locus is perhaps one of the easiest mechanisms understand.
Its job is straightforward: it dilutes all black to brown.
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The dilution is determined by one of four options, in order of dominance:
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Dark Brown (aka Dark Chocolate) - B(D):
​One copy of this allele turns all black to a dark brown.
Note: Heterozygotes tend to be darker than homozygotes.
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Light Brown (aka Light Chocolate) - B(L):
One copy of this allele turns all black to a light brown.
Note: This shade of dilution is commonly seen in the Toggenburg breed.
Wild Type - B(+):
The wild type allele causes no change, all eumelanin remains black.
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Medium Brown (aka Liver Brown/Red) - B(b):
Two copies of this allele changes all black to a medium brown.
Note: This shade is slightly more rich than the other two browns, which are more flat.
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Often, the distinction between light and dark chocolate modifiers is not made, and they are collectively referred to as "chocolate".
 Dark Chocolate - B(D) |  Light Chocolate - B(L) | Wild Type - Black - B(+) |
|---|---|---|
 Liver Brown - B(b) |
EXAMPLES:
Buckskin without a black modifier
Buckskin with dark chocolate modifier
Swiss without a black modifier
Swiss with light chocolate modifier
Blackbelly without a black modifier
Blackbelly with liver red modifier
MOONSPOTS + DAPPLES
Moonspots, also known as Dapples, are incredibly unique and distinct markings found in goats. They typically appear rounded in shape and are randomly scattered across any pigmented coat color. While moonspots can come in various colors, they're often nearly white, tan, or cream-colored.
Interestingly, moonspots tend to be darker in kids compared to adults. Kids commonly have moonspots that are grey, brown, or nearly black, which typically lighten to cream or tan as they grow into adulthood.
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Moonspots can also overlap and make some fascinating shapes and patterns.
Goats can be minimally or extensively moonspotted.
Moonspots are dominant.
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Note: White patterns conceal moonspots, as white is a complete lack of pigment.
 Dominant Black - E(D) Can be E(D)E(D) or E(D)E(+) or E(D)E(e) | Wild Type - E(+) Can be E(+)E(+) or E(+)E(e) | Recessive Red - E(e) Can only be E(e)E(e) |
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WHITE PATTERNS
White patterns are frequently observed in goats, with numerous variations present. These patterns can range from minimal expression, involving just a few hairs, to maximum expression, covering the entire goat in white.
Some goats may even display multiple white patterns simultaneously, resulting in quite unique markings. It is important to know that white patterns conceal any underlying base pattern, often making it challenging, if not impossible, to determine the goat's true markings.
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Much remains unknown about white patterns and their inheritance; however, most are considered dominant, with a few being recessive. Due to the difficulty in distinguishing between them, they are often grouped under one category for simplicity called "White Patterns".
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We know the Agouti Locus acts like the base layer of paint and Extension Locus acts like the top coat.
White Patterns act as Wite-Out, a white layer that covers up or masks whatever is underneath!
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Note: While "white patterns" are often scientifically labeled as "white spotting," I'll refer to them simply as "white patterns" here to avoid confusion with the terms "spotting" or "spots" which is commonly used to describe Moonspots or Dapples.
Dominant Black - E(D) Can be E(D)E(D) or E(D)E(+) or E(D)E(e) | Wild Type - E(+) Can be E(+)E(+) or E(+)E(e) | Recessive Red - E(e) Can only be E(e)E(e) |
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COMBINATION PATTERNS
Combination Patterns are unique to the Agouti Locus.
The majority of Agouti patterns exhibit co-dominance, meaning that if a goat carries two different Agouti patterns, both patterns' pheomelanin (tan) areas will be expressed.
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As a quick review, goats inherit one allele from each parent for each locus:
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If a goat inherits two identical alleles for a locus, they are homozygous.
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If a goat inherits two different alleles for a locus, they are heterozygous.
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Combination patterns arise only in heterozygotes at the Agouti Locus.
(with the exception of those heterozygous with Gold or Recessive Black)
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Pheomelanin (tan) is dominant to eumelanin (black). This means that if two Agouti patterns are present, the pheomelanin of both patterns will be expressed, overriding the eumelanin of either pattern.
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Note: In some cases of combination patterns, pheomelanin may leak, resulting in a reddish-brown hue with hints of eumelanin showing through. I will provide examples of this below.
Dominant Black - E(D) Can be E(D)E(D) or E(D)E(+) or E(D)E(e) | Wild Type - E(+) Can be E(+)E(+) or E(+)E(e) | Recessive Red - E(e) Can only be E(e)E(e) |
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ORDER OF DOMINANCE
We've explored various mechanisms, and you might be wondering about their order of dominance!
From least to most dominant:
Agouti --- Extension --- Moonspots --- White Patterns
For anyone wanting a very easy explanation of the order of dominance...
Imagine you're painting a picture of a goat.
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1. AGOUTI:
First, you lay down the base coat, deciding where the tan and black colors go.
That's like the Agouti Locus, setting the foundation for the goat's color.
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2. EXTENSION:
Next, you add another layer on top, choosing if this layer will be black, clear, or red.
This top coat is like the Extension Locus, giving the final touch to the base color.
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3. MOONSPOTS:
Then, you sprinkle some extra decorations, like glitter, all over the goat's coat.
These are the Moonspots or Dapples, adding a special touch to the painting.
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4. WHITE PATTERNS:
Finally, you take out your Wite-Out and cover up any parts of the painting you want to change.
That's the White Patterns, masking whatever's underneath with a solid white color.
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In the world of goat color genetics, each 'paint' layer has its role, from laying the base to adding the finishing touches! That is what makes every goat truly unique!
Dominant Black - E(D) Can be E(D)E(D) or E(D)E(+) or E(D)E(e) | Wild Type - E(+) Can be E(+)E(+) or E(+)E(e) | Recessive Red - E(e) Can only be E(e)E(e) |
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