The Genetics of Color
AKC and Parent Club Breed Standard:
The Labrador Retriever coat colors are black, yellow and chocolate. Any other color or a combination of colors is a disqualification. White hairs from aging or scarring are not to be misinterpreted as brindling.
Black - Blacks are all black. A small white area on the chest is permissible
This comes from the ancestor of the Labrador Retriever, the St. Johns Water Dog. The earliest photo of a Labrador Retriever is of "Nell" taken in 1899 (see "Know Your Breed"). You will also sometimes see white spots on the feet; this is found in the descendants of English Dual Champion Banchory Bolo (1915 – 1927) and are called "bolo marks".
Yellow - Yellows may range in color from fox-red to light cream, with variations in shading on the ears, back, and underparts of the dog.
There is no such thing as a "White" Labrador; it is a Yellow Lab with a white or cream colored coat; likewise, there is no such thing as a "Fox Red" Labrador; it is a Yellow Lab with a reddish coat. A Yellow Lab with a dark chocolate nose is actually genetically a Chocolate dog with a yellow coat.
Chocolate - Chocolates can vary in shade from light to dark chocolate; a white "ring" around the tail is common and typically falls out with the puppy coat. Chocolate with brindle or tan markings is a disqualification. Chocolates have "chocolate" noses (formerly called Liver), eye rims and pads.
Disqualifications from the Breed Standard
cannot be "shown" in Conformation Competitions
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A black with brindle markings or a black with tan markings is a disqualification. (A small white spot on the chest is permissible.)
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Eye rims without pigment.
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A thoroughlyy pink nose or one lacking in any pigment. (Traditionally called a "Dudley".)
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Any other color or a combination of colors other than black, yellow or chocolate as described in the Standard.
Any other color or a combination of colors other than black, yellow or chocolate as described in the Standard. It is important to note that brindling, tan points, white blazes on the chest or on the rear of the feet and mosaics are still Pure Blooded Labrador retrievers. Before we were able to understand the genetics of color, it was said that these were the product of “miss-mates” or accidental breedings with a dog other than a Labrador. Now we know that that is not the reality. As time goes on, we are able to genetically test for more of the color genes.
Note: Disqualified dogs (from Breed Competitions) are still Purebred Labradors and still make wonderful companions, however, breeders should not be purposefully breeding to produce the off-standard traits.
Predicting a Litter's Colors
I am often asked how we know the colors of the puppies in any given litter. The short answer is that we genetically test most of our Labradors to see what colors they may carry. But usually, there are a few follow up questions. This page hopefully helps to answer those follow ups..... Let's begin with the color of the nose, eye rims and pads of the feet.
A Black or Yellow Lab with black Nose, eye rims and pads carries a visible "B" gene and second "hidden" copy of that gene. The hidden copy may be either "B" or "b".
Phenotype is what we see and genotype is what we don't see. Each Labrador has their visible color and each has their hidden color or colors.
A Black or Yellow Labrador carries the dominant "B" inherited from one of the parents. The second copy of B is hidden. It may be either the dominant "B" or the recessive "b". This B gene determines the color of the Labradors nose, pads and eye rims. "BB" will look the same as "Bb" in this Labrador, but the Labrador who carries "Bb" instead of "BB" is hiding the color Chocolate.
If the Labrador who carries "Bb" is mated to another Labrador who carries "BB", all the puppies will have black noses, pads and eye rims. BUT, if the Labrador is mated to another "Bb", some of the puppies will have a chocolate nose, pads and eye rims. This is because some of the puppies will get a "B" from each parent; some will get "B" from one and a "b" from the other while others will get a "b" from both parents - these ("bb") are the ones who will have chocolate noses, pads and eye rims.
The "E" gene determines the coat color of the Labrador. E will express black as long as the dog carries a dominant B. Two copies of the recessive "e" will shut of black and the coat will be Yellow.
There is a second gene that we test to determine the color of a litter of puppies. This is the "E" gene. It works in same manner as the "B" gene but it actually determines the color of the coat and it works with the "B" gene .
The Black Labrador in the "B" gene example above carries the dominate "E" gene. We know this because we can see his Black coat. The Yellow Labrador with the black nose, eye rims and pads has inherited two copies of the recessive "e" which shuts off the ability of the "B" gene to express itself as a Black coat; again we know this because we can see her Yellow Coat.
From this we can make a pretty good start at guessing at the Genotype of each of the three Labradors in the "B" gene example above but we cannot know the full Genotype just yet. The "*" indicates what we don't yet know.
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The Black Lab is B*E*
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The Yellow Lab with the black nose, eye rims and pads is B*ee
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The Yellow Lab with the chocolate nose, eye rims and pads is "bbee"
But now, we also have the fourth example....the Chocolate Lab
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The Chocolate Lab is bbE*
Note that we don't know the mode of inheritance in all but one example above. There are two ways to learn what should be in the place of the "*".
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The old fashioned way was to simply breed a dog to other dogs and wait to see what colors they would throw. A Black Dam mated to one Black Stud might throw just Black coated puppies; but, with another Black Stud, she might throw two colors and with a third, maybe all three colors. In the latter case, we would know that her Genotype was BbEe.
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The way we do it now is to genetically test the B and E genes in our dogs (of course, we don't need to test the E gene in a Yellow dog because we already know that the Genotype is "ee".)
If you'd like more information on how we can attempt a guess as to how many of each color puppy would be born to a pairing of genotypes, see the chart linked below.
But, that is just the start of genetic testing for coat colors. Other genes determine the shading of the Yellow coated Labrador (from Fox Red to White) as well as determine whether the Labrador will have white spotting or the rare brindling and mosaic coat. You read about Genetic Panel Testing on our Genetic Health Testing Page and how it is changing how breeders can determine things such as the co-efficient of inbreeding more accurately; well, it is also helping us discover why, every so often, we have these rare coat colors pop up in a breeding. The link above opens on a new page so you can quickly find your way back here to read the rest of this page....
S- Locus - White Spotting in the Pure-bred Labrador retriever
K Locus - Solid Color
A - Locus - "Reds"
Genotype is hidden while Phenotype is seen
B = Black; b = Chocolate; E - no Yellow; e = Yellow; KB = solid; S=White
(There is also "A" which is responsible for the red tint seen in some dogs and for the tan point, brindle and mosaic labradors and "C" which determines the shading in the Yellow coats, but for the purpose of this page, we are focusing only on the genes named above.)
In the first part of this page, we learned about Genotype as it pertains to Black, Yellow and Chocolate Labradors. So, let's take a look at the full genotype where color and pattern are concerned.
A Black Labrador can have one of the following genotypes:
BB/EE/KB-KB/SS - no hidden Chocolate or Yellow, Solid Colored, may express a few white hairs
Bb/EE/KB-KB/SS - hidden Chocolate, no hidden Yellow, Solid Colored, may express a few white hairs
BB/Ee/KB-KB/SS - no hidden Chocolate, hidden Yellow, Solid Colored, may express a few white hairs
Bb/Ee/KB-KB/SS - hidden Chocolate, hidden Yellow, Solid Colored, may express a few white hairs
BB/EE/KB-KB/Ss - no hidden Chocolate or Yellow, Solid Colored but with white spotting
Bb/EE/KB-KB/Ss - hidden Chocolate, no hidden Yellow, Solid Colored but with white spotting
BB/Ee/KB-KB/Ss- no hidden Chocolate, hidden Yellow, Solid Colored but with white spotting
Bb/Ee/KB-KB/Ss - hidden Chocolate, hidden Yellow, Solid Colored but with white spotting
I'm not going to list all the genotypes for a Chocolate or Yellow Labrador, but you have gotten a good idea of the process, so let's move on to those white spots and the rare brindle or mosaic Labradors and the genes responsible for them.
The Genetics of Color in the Labrador retriever
DNA has proven that these miss-marked dogs are pure-bred Labradors with the health and temperament of their solid colored siblings.
The Tan Point, Brindle, or Mosaic Labrador are rare.
This page focuses more on the White Spotting which is more commonly seen.
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Many a breeder and many a poor Dam has been accused of miss-mating when a litter includes a few Black or Chocolate Dogs with white spotting on their chest or when a puppy or two were born with tan points, brindling, or even those very rare "mosaics".
No matter how the Breeder might protest that there was no way any puppy in the litter couldn’t be from the Sire they had used, the accusers would walk away shaking their heads still believing that puppy just couldn’t be a pure-bred lab. Buyers walked away and Breeders scorned other breeders…until it would happen in one of their own litters.
You will even see debate raging on various social media platforms today despite all the knowledge that we have gained from genetic testing. Those who still maintain that a miss-marked Labrador is the result of an accidental pairing do so out of an ignorance of the science which proves them wrong.
If you’ve ever learned the history of the Breed, you know that the ancestors of the Labrador were black and white coated St. Johns Water Dogs. With the goal of producing a solid black dog, the old-timers would only breed dogs with the most black in their coats; eventually, they were able to breed solid black to solid black until they consistently were producing litters with mostly solid black dogs. But even then, there would be a few “liver coated” dogs or “yellow coated” dogs; and sometimes, a black dog with white on its chest.
Those old-timers continued for many generations to breed black to black removing the other colored dogs from their breeding programs but the gene responsible for the expression of white hairs was still being passed down generation to generation just as the genes for liver (chocolate) and yellow coated dogs were.
Because the old-time breeders bred only black to black, the gene pool was small enough that most of those solid black dogs carried two copies of "S" and no copy of "s" so the white inherited from the St. Johns Water Dog did not “express” itself very often. And this rarity is what led to the common belief that a “miss-mating” had taken place and the poor black or chocolate lab with the white on its chest or the yellow with a lot of white expressed was a “mutt”.
Eventually, a closed kennel which produced litters bound to provide some service, would from time to time see white spots on the chests of Labrador puppies born under strict controls; controls that meant that there was no possibility of a miss-mating. This was evidence that there was some recessive gene that was causing pure-bred dogs to express those white hairs.
Science eventually proved that to be true, but even before that, the AKC and Labrador Retriever Clubs rewrote the Breed Standard to state that “a white spot on the chest is acceptable but not desirable” in dogs that were shown in breed competitions acknowledging that these dogs were in fact, pure-bred Labradors.
We know now that white hairs originate from the S Locus. The non-mutated form (S) makes it possible for a dog to express a few white hairs or none at all. It is a roll of the dice. The recessive version (s) of the gene means that the dog will express what is known as “white spotting”. And a dog with two copies of the mutated version (ss) will be solid white.
The two main genes for coat color in Labradors are "B" and "E" and each puppy receives one copy of each gene from each parent; these genes follow the Dominant/Recessive expression where "B" cancels "b" and "E" cancels "e". So, a puppy getting BB is not going to be Chocolate nor is a puppy getting Bb because the "B" cancels or hides the "b".
It is the same for the "E" gene; in order for a dog to be yellow, it must get two copies of "e". The "S" gene however is co-dominant and therefore only one copy of the mutated "s" will result in expression of the recessive which is the expression of white.
And we also know now that the “red” that is sometimes seen in a Black or Chocolate coat and quite often in the traditional Yellow coat in what is known as the “Fox Red” comes from the “A” locus as does the more rare tan points and brindling and even perhaps the mosaic.
So, if someone tells you that your pure-bred puppy with some white on it's chest or a white ring around its tail isn’t pure-bred, all you need to reply is “DNA says differently”. Your puppy is every ounce a pure-bred Labrador from genetically tested parents descended from the black and white St. Johns Water Dog - the first Labrador retrievers.