The hair color on Choco's can vary slightly, but, there is no getting around the LIVER Colored nose. The nose, eyeliner, and pads should be some variation of brown, whether Hershey type chocolate or a more diluted chocolate as in chocolate fawn/sable. If the nose is not liver(brown) it is NOT A TRUE CHOCO! Chocolate color in dogs is no more than a Diluted Black dog. Contrary to popular thinking, the Chocolate bb (Brown/Liver) gene is really NOT a choco gene. It is a dilution gene which dilutes Black to Brown. For the Chocolate Gene to make, if you will, a dark chocolate dog, the BLACK base has to be there to be diluted. The eyes are often light gold, green, blue, or gray. In addition to the nose color, DNA Color testing will reveal the "bb" alleles in CHOCOLATE dogs. Each parent also contributes one of their two dilution factor genes to their offspring - either a brown (b) gene or a non-brown (B) gene. Chocolate parents (bb) can contribute only a brown (b) gene and non-brown parents (BB) can contribute only a non-brown gene (B). Choco Carriers can either contribute a non-brown (B) or a brown (b) gene. For more info, please refer to the Official Rare Color Chart.
Genotype for Chocolate Gene: [bb]
Overview: Chocolate Bulldogs are diluted black dogs from a different dilution gene than the blue. The chocolate coat should be shiny and look brown against black objects or in the sun, unless the seal gene is involved which can give different undertones to the coat. These dogs may or may not have a fawn undercoat when the hair is rubbed backwards. The nose, footpads, & eyeliner are always chocolate, even in the chocolate fawn.
Brown aka Chocolate
BB, Bb, bb
TYRP1 Gene. There are two alleles 1. B dominant full base color 2. b recessive brown
TYRP1 is a modifier of eumelanin, not a dilution gene as in blue (dd). The dilution gene affects how dense the pigment is, which makes it appear pale as if you mixed white into black paint making gray. The chocolate bb does not dilute, but changes the shape of the molecules of the pigment. The different shape reflects light in a different way and therefore changes the black to chocolate.
When you have a bb dog, black pigment is modified to chocolate. If your dog is red or yellow base, the bb does not modify the hair color, but does modify nose, eyerims, and foot pads from black to chocolate and eye color to amber or gold.
BB: Does not carry chocolate, full base color, cannot have chocolate offspring
Bb: Dog is base color and carries 1 copy of chocolate
bb: 2 copies of chocolate, full chocolate
The hair color on Chocolates can vary slightly, but, there is no getting around the LIVER Colored nose. The nose, eyeliner, and pads should be some variation of brown, whether Hershey type chocolate or a more diluted chocolate as in chocolate fawn/sable. If the nose is not liver (brown) it is not a true chocolate. Chocolate color in dogs is basically a modified Black dog, where black is modified to chocolate. For the Chocolate Gene to make a dark chocolate dog, the Full Black base has to be there.
The chocolate gene affects black pigment only. If a dog is bb, all of the black in the coat will be turned to chocolate. This includes all patterns. Chocolate turns the nose and eye color, usually to an amber, yellow, or gold color. The nose color is the best way to tell chocolate from a black or blue. When you combine a chocolate dog with a blue dog, bb + dd, you get a lilac, which is the color of a Weimaraner.
Chocolate is recessive, so it takes 2 copies to present on the dog. If a dog is full black base and is bb, all the black in its coat will become a chocolate. Bb and BB have no visible effect.
As if this were not confusing enough, I have now been advised that there are 3 Sequences to the b genotype. There are a number of different versions of the b allele, but all of them result in the same coat color. These variations mean you can have either b, b2, or b3 on your dog’s DNA. This can be on one or both sides of the complete gene.
Therefore, it is possible to have your dog dna any one of the following types:
Bb Bb2 Bb3 bb bb2 bb3 b2b b2b2 b2b3 b3b b3b2 b3b3
Some labs recognize all 3 sequences and some don't, so you could have a b2 or b3 on your dog and not know it.
UPDATE! 2020 There has been a new Variant discovered that can be tested for, which explains the many Chocolate French Bulldogs that tested BB. It is called the Cocoa Gene.
Non-Testable (now testable): coco
Pre 2020: The French Bulldog and Chocolate Color
Our main topic here is testable and non-testable chocolate color in French Bulldogs. For the purposes of this article, we will use the term “Normal Chocolate” for the testable, and “Mutated Chocolate” for the non-testable. The Normal Chocolate is the same test that has always been around for chocolate (brown) for years and is used in many breeds. The Mutated chocolate is actually more common in FB, but the gene/mutation/modifier has yet to be found.
For many years there have been visually chocolate FB’s that have tested BB…non chocolate, so there ARE chocolate FB’s that definitely have chocolate hair and a chocolate nose that test BB. This Mutated Chocolate Gene or Modifier for this type chocolate has yet to be discovered and therefore no test is available at this time for those dogs. Recently, we have quite a few FB lines that do test Bb or bb, and the dogs in those lines that test bb actually look Chocolate.
A lot of people/breeders claim that these lines are mixed with other breeds to have brought the testable b in, even though these dogs are visibly chocolate, which is ironic since these same ones claim they have chocolate FB’s that test BB and also do not look chocolate but rather, black, faded black, or seal with a bronze or other color undertone.
Not one of these ones can produce any proof that the testable lines are mixed, while at the same time, many of these Bb or bb dogs have been parentage DNA tested and have been found to be 100% FB. Therefore this claim of mix breeding is 100% unsubstantiated.
From the Geneticist: "The French Bulldog has two ways to be chocolate. One we can test for, but has been historically rare in the FB, and one that is still unknown, and seems to be the most common way the FB are chocolate. Recently, we are seeing more FB show up with the testable chocolate."
Not unknown any longer! Read on.
Cocoa: A brown coat color resulting in a slightly darker coat than the brown color caused by other variants. This color is seen in French Bulldogs and was previously referred to as non-testable chocolate.
NN: does not have the cocoa variant.
N/co: carries one copy of the Cocoa Variant
co/co: carries 2 copies of Cocoa
PARTIAL EXCERPTS FROM UCDAVIS
There are several known variants that result in the chocolate color in dogs. These known variants do not account for all chocolate in dogs.
The cocoa variant is a different gene and is therefore not TYRP1.
In French Bulldogs, a variant associated with a visually distinct chocolate phenotype was identified in the Hermansky-Pudlak syndrome 3 (HPS3) gene. Dogs with the HPS3 gene variant are visibly darker brown than the phenotypes associated with the previously described TYRP1 brown allele (b).
The canine cocoa variant is a single base change in the HPS3 gene.
The variant associated with the cocoa phenotype is recessive. Thus, two copies must be present for the dog to appear chocolate.
Data suggest one copy of cocoa (carrier) and one copy of any of the previously described gene variant (carrier) for brown will not result in a brown phenotype. Dogs with two copies of the cocoa variant may be cocoa, however the final phenotype of the dog is dependent on the alleles at other coat color loci.
At this time the interaction of cocoa and the other brown allele is not understood. Therefore, it is not yet possible to predict the phenotype of a dog with two copies of cocoa (co) and two copies of the TYRP1 brown (b).
At this time, it is also unknown if the cocoa variant is found in other dog breeds.
In this first photo our Choco Baby Scrunchy on the left next to her sister who will have a black nose. It is very easy to see the light brown nose pigment coming in.
Interesting tidbit: Scrunchy went on to become mother to the Worlds First AKC Purple Lilac English Bulldog....Extreme Z!
In this photo we have our same black nosed girl on the left, our Chocolate Boy Semi in the middle, then our Chocolate Girl Truffy on the right.
More photos at 4 weeks old...more pigment coming in. Black nose puppy on right.
Our 3 Chocos at 8 weeks old
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