Here you will find some interesting facts on French Bulldogs and the different ways they can express their colors and patterns! Best dogs on the planet!

What is French Bulldog color?

So, you may see a bunch of what looks like code written in letters to describe a french bulldogs color? Let me see if I can explain a little bit. A French Bulldog is often times looked at as just a “visual color” But a lot of research has been done involving what color dna a bulldog actually is to determine what colors you can get from a pairing. There are standard colors and rare colors. Below you will find a break down of those colors and their corresponding “letter codes”

First off a little information about color genes and which ones are “recessive” (meaning you need 2 copies to create it visually) and which ones are dominant (meaning you only need one copy to visually create it).


Brindle is referred to as a “pattern” because it will present as “stripes” which color is determined by other Locuses that are genetically present in the dog. So Brindle is a dominant gene and ONLY requires 1 copy to present itself. So, a dog that genetically carries even 1 copy of Brindle, it is considered brindled, even if the brindle doesn’t present itself on the dog. Brindle is genetically referred to as KBR or in some tests K or KB. It is also referred to many times as being a “dominant black gene” . KY is the absence of this gene. So a dog who carries only one copy of brindle can be referred to as KBR/KY. A dog that carries no copies of brindle at all, are referred to as KYKY. The most important thing to note here is that EVERY SINGLE solid color “looking frenchy” IS genetically a brindle unless they are fawn, tri, or the rare a/a combination. People will often try to refer to them as “blue dog” or “black dog” because brindle has become undesirable in breeding programs around the world. But it is important to note that these dogs are genetically brindle even if they express a solid looking color and show no stripes at all. And they are guaranteed to produce brindles. If you are trying to avoid brindle, it’s always important to ask for dna.

Pied or Piebald:

Pied is a recessive pattern (or lack thereof) I like to refer to pied as “the delete gene” . Pied requires 2 copies of S (ss) to create a visually pied dog. One copy of pied (s/n) will be referred to as a pied carrier. Pied will present itself in many different ways, but will always delete at least 50% of the dogs actual “color” The gene can delete the color wherever it wants. It can also create what is referred to as “an extreme pied” meaning no visual color on the dog. Those dogs will be solid white! There is also what is referred to as a “saddle pied, Irish pied, or blanket pied” these dogs are genetically not pied. They carry 1 copy of pied. These dogs often have solid color on the backs and heads and their chest, around the neck and all the way up the legs will be white. In essence, it’s simply the max amount of white markings that 1 copy of pied can present (<50% of the body will be expressed in deleted pigment)


Merle is also a pattern gene. There are many many different variations of Merle. The genetic letter for merle is “m”. The Merle pattern is a pattern that dilutes certain areas of the dogs color and makes it appear as a different color. You only need 1 copy of Merle to be present to make a visual Merle. Merle is a very in depth studies for a lot of people because there are up to 7 different type of it. Some of those are Ma, Mc, Mh and more. You can not breed 2 longer merle lengths together as this pairing can create a lethal combination that may result in deafness, blindness or worse. I am not an expert on merle, I would definitely recommend doing a lot of research on merles if you ever decide to purchase one for breeding. Tweed merle is a phenotype of merle expression. It happens when merle dilutes the solid pigmented areas to 3 or more shades of the base color. There is no genetics for tweed, it’s just something that happens. It does happen more on dogs that are on the longer length of the merle scale such as harlequin merle. Mosaic merle is a term for a mutated merle gene. Mosaics will present with 1 non copy of merle and then 2 or more mutated copies of merle on the second allele. For example, a mosaic merle can be m/Mh(Mc). This interesting phenomenon occurs when the color is forming in the embryo. The merle will split off into another length and then share that allele with the dominant copy of the merle. A mosaic dog can pass only 1 of its merle variants to its offspring. A mosaic dog who is genetically m/Mh(Mc) will pass either m (non merle), Mh (Harlequin Merle) or Mc (Cryptic Merle) to each one of its offspring. In closing the merle subject, another important factor to remember is that the shorter the length of merle, the less apparent the merle “patches” will be. Cryptic merle will never dilute any pigment. It’s simply not a long enough length to have any effect on the pigment. That being said it is important to note that a Cryptic Merle will appear AND breed as a NON MERLE. Cryptic merles are perfectly safe to breed to another merle as, again, they appear and breed the exact same as a NON merle dog. Lastly, I’d like to discuss “hidden merle” and “ghost merle” terms. A hidden merle is a merle dog that has been covered by cream or deleted by pied. A cream dog that is genetically merle will not express a visual Merle pattern because it is “blanketed” by the cream. A pied dog, especially an extreme pied, can delete all the pigment where you would see merle, thus “hiding” it. No other 2 dogs besides a cream or a pied can have “hidden merle”. Now moving on to “ghost merle”. Ghost merle is a term that refers to something fading the merle to a near non existent visual pattern. Fawns and sable dogs that are merle will often times appear very merle at birth and then the patches will fade over time. This is because the fawn color sort of washes out the base pigment therefore washing out the visual Merle patches. Ghost merles can also signify merle of a shorter length such as “M+” the shorter length will not allow the merle patches to be as bold as the longer length alleles can.


Mask is genetically referred to genetically as “Em”. You only need one copy of this gene to have a dog with a visual mask. Now, that being said, certain things will cover a mask, such as brindle, or pied, in that case you would have to test the dog to see if it carries a copy of Em. The interesting thing about mask is that the cream gene will delete copies of mask. Confusing right? So what happens is this, when you have a dog that carries 1 copy of cream, it will automatically delete one copy of mask if it is present. A dog that is visually cream (two copies of cream “ee”) there will absolutely be NO mask. A dog can also be “maskless” or carry no copies of mask regardless of the fact if they carry cream or not. The genetic code for maskless would be n/n on the EM locus or as some refer to it as E/E. Since the cream always deletes a copy of mask if present, you may also see it put as “Em/e”.


Cream is a recessive gene meaning it needs 2 copies to create a visual cream. The genetic letter code for cream is “e” . I like to think if cream as a blanket or “cover” gene. A dog can genetically be any color and be covered in cream. So here is where genetic testing comes in real handy! So you can have a dog that is blue tri, and you would never see it if it carries “e/e” because the 2 copies of cream will cover the entire dog in a cream suit!


A true blue dog will genetically test showing “dd”. d is referred to as a dilute color. It is also recessive, meaning you must have 2 copies of “d” to create a visually blue dog. A dog that carries blue will genetically test as Dd, meaning it is a carrier. A carrier of blue can create a blue offspring if it is paired with another dog that is either dd or Dd.

Chocolate (cocoa):

The genetic letter for chocolate is “co”. Chocolate is a recessive gene meaning it does take 2 copies of chocolate to make a visually chocolate dog. A carrier of chocolate will be referred to as “Coco” . This Cocoa chocolate is a newly discovered locus! Until recently, there was no dna test for it. Chocolate causes a phenomena known as “red eye glow” . If you shine a light into the eyes of a chocolate dog, they will reflect the light in a bright red reflection! They look like little demons! Some still refer to this chocolate as “non-testable chocolate” because for so many years it was not able to be tested for and the term was originally created to differentiate it from the “testable chocolate” aka rojo that was newly introduced into the frenchy breed

Rojo chocolate:

There is a relatively new color to hit the French Bulldog scene, Rojo Chocolate also known as “testable chocolate” (as the previous cocoa chocolate was non testable). If a dog carries the gene for rojo chocolate, it will genentically test as “Bb”. The testable chocolate is a bit of a different shade of chocolate than the “cocoa” is. It seems to be bit “more red” in appearance. And just like “cocoa” chocolate, you will need 2 copies to make a visually rojo chocolate dog.


Lilacs are very interesting genetically! They actually require “coco dd” to create a true lilac. That means that you have to have a double copy of blue, and a double copy of coco present in the same dog to create the “lilac” color.


This lilac referred to as “isabella” is created the same way the previously mentioned lilac is created, but it is made with the “rojo chocolate”. It does present in a slightly different shade than the aforementioned lilac color due to the rojo chocolate having a “more red” tint. It will genetically test as “dd bb”

New shade:

Because this is a term being used by a lot of breeders, I’ll list the definition here New shade is a term meant to describe a dog that is genetically bb coco. It’s a combination of 2 copies of both of the chocolates.

New shade Isabella:

New shade isabella is genetically the same as New shade but it adds 2 copies of blue. So the dna will be dd coco bb. There has been some people calling a “New New shade” lol and yes this is a dd coco bb dog with 2 added copies of intensity which is ii. Intensity is simply a color modifier gene. Intensity creates, as you may guess by its name, a more intense or reddish tint to its underlying color partners.


The tri gene is found on the A locus. This gene is responsible for the tan points (like a rottweiler) on a french bulldog. The A locus contains 3 different variations. A visually tri dog will genetically test as at/at. That being said, there is another variation of the A locus referred to as “a” which I will explain later in this article. If the “at” gene is paired with “a” (at/a), you will still have a variation of a visual tri dog. on these dogs, oftentimes the points are smaller and not quite as pronounced. When the at gene is paired with kyky (no brindle) it creates what we call a “sable” dog. Sables are often carriers of just one copy of tri, but sometimes they often express very light colored “tri points”. If a genetically tri dog (at/at or at/a) is present in a dog with even one copy of brindle, the brindle will express inside the tan points and create what we refer to as a “trindle” Sometimes, in a trindle, the brindle will take over those tan points so much so that you can’t even see the tan points at all. In which case, you would have to do a DNA test to see what the dog is genetically.

A gene:

There are 3 different variations of the “a” locus. There is “at” (tri as before mentioned) “a”, and “ay”. These 3 variations can appear in any combination within a dog. “ay/ay” is a non expressed “a” allele. When you have an “ay/ay” dog, the dog will express whatever color is on the “K” locus. Meaning that if the dog is brindle (kbr/ky or kbr/kbr) the dog will appear in a full brindle appearance. If the dog is non brindle (kyky) then the dog will appear fawn or sable. Sable is simply a fawn based dog with various base colored tipped hairs that usually express down the back but can be expressed different places depending on the dog. Some sables are so “tipped” they actually make the dog appear to be tri in appearance. But the top of the head usually gives it away as there will be a more fawn color to that area.


This variation of the “a” locus creates a true solid dog. Meaning, even if it carries brindle, it will not appear. An a/a dog is the only one true “SOLID” colored dog. the “a” gene can be paired with any of the other 2 variants of its locus, but it will ONLY be a solid appearing dog when it is genetically a/a.

Now to explain a little bit farther. Each puppy will receive one color dna gene from its mother and 1 from its father. Only 1 from each parent.

So as you can see here in this chart, these are the possibilities for different pairings. Although this chart is showing the “tri gene” as an example, This also applies to any other recessive gene such as pied, blue, chocolate, rojo, and cream.

Disclaimer: I am not an expert. I would just like to share knowledge that I have gathered from different articles, experts, and my own experience over the years. Color is not the ONLY thing to consider when looking for a puppy, But it is nice to have a basic understanding of your new puppies color make up! And the really cool things that color DNA effects on how your puppy expresses his color!