Exotic Bulldogs
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Complete guide to French Bulldog genetics and breeding

How the genetics we use in our program work: what each dog expresses, what it carries and what a breeding can produce.

Understanding what you see

Each trait, pointed out in photos of our own dogs.

Close-up of Zeus's face Nose rope

Zeus

Big Rope

In breeding circles, this is the name for an especially pronounced nasal fold above the muzzle. In Zeus's photo, it is the fold that forms an arch just above the nose.

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Big Rope is the breeding term for an especially pronounced and well-defined upper nasal fold, which gives the face a very distinctive look.

It is a highly sought-after phenotypic trait within certain exotic French Bulldog lines, and part of the distinctive look of dogs like Zeus.

Its expression varies between dogs: it depends on each dog's structure and genetics, not on a single isolated gene.

As with any Frenchie with defined facial folds, it is enough to include cleaning of the area in its routine, keeping it clean and dry.

Valentino sitting, showing his long coat on the ears, chest and body

Valentino

Fluffy

The term used for a long coat in the French Bulldog. In Valentino you can see it on the ears, chest and body.

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Having a long coat is not the same as being a carrier. In the breed, long hair is associated with variants of the FGF5 gene and is inherited recessively: a dog shows it when it receives the variant from both parents, and a short-haired dog can carry one copy and pass it on.

Valentino's report shows two different long-hair variants (l1/l4): he expresses the trait.

Zeus's face with the light markings above his eyes The “eyebrows”

Zeus

Tan points

Markings of another shade that appear above the eyes, the so-called “eyebrows”, and in other areas such as the cheeks, chest or legs. In Zeus they are clearly visible above the eyes.

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This pattern is associated with the at variant of the A locus. Zeus is at/at: he passes Tan on to all his puppies.

Valentino from behind, with the Merle pattern visible on his back and sides

Valentino

Merle

A pattern of irregular patches, with areas of lighter and darker pigment. In Valentino you can see it across his whole coat.

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His DNA report confirms it: one copy of the merle variant (n/M). With a single copy, the pattern is already expressed. In our program we avoid Merle × Merle breedings.

Genotype and phenotype

Genotype

The dog's genetic information: the two copies it received of each gene, one from each parent. This is what a DNA test shows.

Phenotype

What you see: color, pattern, coat type and physical traits.

Expresses

The trait is visible in the dog.

Carries

It has one copy of the gene without showing it, and can pass it on to its puppies.

Dominant, recessive and carrier

Not all genes work the same way. Some need two copies to show; others are expressed with just one.

A recessive gene: dilution (D locus)

D/D

Non-carrier

No copies of dilution.

D/d

Carrier

One copy: not visible, but it can be passed on.

d/d

Visual

Two copies: the dog expresses Blue.

A gene expressed with a single copy: Merle

n/n

Non-merle

Does not have the variant.

n/M

Visual Merle

With a single copy, the pattern is already expressed.

How to read a DNA test

Each result shows two copies separated by a slash: one inherited from the mother and one from the father.

ResultWhat it meansReading
D/DNo dilutionNon-carrier
D/dOne copy of dilutionCarries Blue
d/dTwo copies of dilutionExpresses Blue
b/bTwo copies of Testable ChocolateExpresses Rojo
co/coTwo copies of CocoaExpresses Cocoa
at/aOne copy of tan and one of recessive blackExpresses Tan · carries a
n/MOne copy of MerleExpresses Merle
EM/eOne copy of mask and one of creamCarries Cream
L1/L4Two long-hair variantsVisual Fluffy

Color genetics

A Frenchie's color is the result of different genes that can be expressed alone or combine with each other. Below we show visually the main colors and patterns we work with, along with the genetic combination associated with each one.

Long-haired Black French Bulldog puppy with a white patch on the chest, sitting in front of a wooden wall

Black

a/a

Pied French Bulldog, white with dark patches on the face and body, sitting on a wooden floor

Pied

S/S

Blue French Bulldog puppy with blue eyes, in a dog bed

Blue

d/d

Lilac French Bulldog female puppy with a lilac-gray coat, lying on a table

Lilac

d/d + co/co

Long-haired Cocoa French Bulldog puppy with a white patch on the chest, sitting on a gray surface

Cocoa

co/co

Rojo French Bulldog puppy, sitting in front of a patterned cushion

Rojo

b/b

Isabella French Bulldog puppy with light eyes and an orange harness, standing on a light floor

Isabella

b/b + d/d

New Shade Rojo French Bulldog puppy with pronounced folds, sitting on a wooden step

New Shade Rojo

b/b + co/co

Long-haired New Shade Isabella French Bulldog puppy with light eyes, sitting on a wooden table

New Shade Isabella

b/b + d/d + co/co

Long-haired Pink French Bulldog, standing on the grass

Pink

A/A

Long-haired cream French Bulldog puppy with light eyes, sitting on a light sofa

Cream

e/e

Lilac Platinum French Bulldog puppy with a light cream coat, standing on a wooden table

Lilac Platinum

e/e + d/d + co/co

Isabella Platinum French Bulldog puppy with a light cream coat and light eyes, lying on a rug

Isabella Platinum

e/e + b/b + d/d

Blue & Tan French Bulldog puppy with blue eyes, sitting on a sidewalk next to the grass

Blue & Tan

d/d + at/at

Lilac & Tan French Bulldog puppy with light eyes and its tongue out, standing on a leafy path

Lilac & Tan

d/d + co/co + at/at

Cocoa & Tan French Bulldog puppy, standing on the grass in the sun

Cocoa & Tan

co/co + at/at

Long-haired Rojo & Tan French Bulldog, standing on a rock

Rojo & Tan

b/b + at/at

Zeus, Isabella & Tan, resting on the sofa

Isabella & Tan

b/b + d/d + at/at

Zeus

New Shade Rojo & Tan French Bulldog

New Shade Rojo & Tan

b/b + co/co + at/at

Long-haired New Shade Isabella & Tan French Bulldog puppy, standing on a wooden board

New Shade Isabella & Tan

b/b + d/d + co/co + at/at

Pied Merle French Bulldog puppy with white areas on the chest and legs, held on a pink blanket

Pied Merle

S/S + n/M

Blue Merle French Bulldog puppy sitting on a light wooden floor

Blue Merle

d/d + n/M

Lilac Merle French Bulldog puppy with light eyes, sitting on a blanket

Lilac Merle

d/d + co/co + n/M

Long-haired Cocoa Merle French Bulldog puppy, sitting next to another puppy on a white surface

Cocoa Merle

co/co + n/M

Rojo Merle French Bulldog with a red collar, sitting on a tiled floor

Rojo Merle

b/b + n/M

Isabella Merle French Bulldog puppy standing on an upholstered bench

Isabella Merle

b/b + d/d + n/M

Long-haired New Shade Rojo Merle French Bulldog puppy, sitting on a stone step

New Shade Rojo Merle

b/b + co/co + n/M

Long-haired New Shade Isabella Merle French Bulldog puppy, in profile on a light cushion

New Shade Isabella Merle

b/b + d/d + co/co + n/M

Long-haired Blue & Tan Merle French Bulldog puppy with blue eyes, standing on a white armchair

Blue & Tan Merle

d/d + at/at + n/M

Lilac & Tan Merle French Bulldog puppy with blue eyes, standing on a dirt path

Lilac & Tan Merle

d/d + co/co + at/at + n/M

Rojo & Tan Merle French Bulldog puppy with light eyes, sitting on the grass next to a white fence

Rojo & Tan Merle

b/b + at/at + n/M

Long-haired New Shade Isabella & Tan Merle French Bulldog puppy with light eyes, sitting on a cushion

New Shade Isabella & Tan Merle

b/b + d/d + co/co + at/at + n/M

Long-haired New Shade Rojo & Tan Merle Intensity French Bulldog, sitting on a light armchair

New Shade Rojo & Tan Merle Intensity

b/b + co/co + at/at + n/M + Int/Int

How a color is built

The colors in the gallery come from combining just a few genes. When a dog has two copies of more than one recessive gene, their effects add up and produce a new color.

b/b + co/co

New Shade Rojo

b/b + d/d

Isabella

d/d + co/co

Lilac

b/b + d/d + co/co

New Shade Isabella

Black (a/a) and Brindle

a/a — Recessive Black. When no other gene modifies its color, an a/a dog is expressed as a solid, deep and uniform black. If genes such as Chocolate, Blue or Cocoa come into play, that base color changes and produces other exotic phenotypes. A completely black a/a, with no other visible colors or patterns, is uncommon today within modern exotic Frenchie lines.

Brindle. A different pattern, associated with the K locus, with dark streaks or stripes over the coat. It should not be confused with a solid a/a black. In programs focused on clean exotic colors it may be undesirable, because it visually interferes with other colors and patterns.

a/a Black

Solid, uniform black.

Brindle

Streaked pattern.

Tan

Tan is a pattern, not a color: lighter markings above the eyes, on the muzzle, chest and legs, which combine with any base color.

Intensity

Intensity modifies the expression of red and tan pigments: certain areas may look lighter or softer, with transitions into caramel and cream tones.

Intensity

Two copies: expresses the effect.

Intensity Carrier

One copy: carries it.

No Intensity

No copies.

Merle

Merle works differently from recessive genes: with a single copy (n/M) the dog is already a visual Merle. The pattern creates areas of lighter and darker pigmentation within the coat, with variations unique to each dog.

In our program we do not do Merle × Merle breedings.

A puppy with two copies of Merle (M/M) has a higher risk of hearing and vision problems. That is why we only breed a Merle dog with a partner confirmed as non-Merle by DNA.

Example: Valentino, n/M

Pied

A pattern with large areas of white combined with pigmented areas. A dog can be visual Pied or carry it without expressing it; knowing its genetic status helps anticipate which patterns could appear in a litter.

S/S

Visual Pied

n/S

Pied Carrier

n/n

Non-carrier

Platinum / Double Cream

A Platinum Frenchie expresses two copies of the cream gene (e/e), which can visually hide the base color it carries genetically.

Unlike a traditional cream with dark pigmentation, a Platinum carries a diluted color beneath the cream. That is why it can have lighter pigmentation on the nose, lips, eye rims and paw pads.

Lilac Platinum

Beneath the cream: Lilac.

Isabella Platinum

Beneath the cream: Isabella.

New Shade Isabella Platinum

Beneath the cream: New Shade Isabella.

Because cream can hide those colors, the DNA test is what confirms which genetics the dog really carries.

Example in the color gallery: Lilac Platinum

Fluffy

To be a visual Fluffy, a dog needs two compatible long-hair variants, one from each parent. They can be different variants: L1/L4 is a visual Fluffy.

L1/L4

Visual Fluffy

L/L4

Fluffy Carrier

L/L

Short coat

Pink

Pink is recessive: it needs two copies to be expressed. With a single copy the dog does not show it, but it is a Pink Carrier and can pass it on to its puppies.

A/A

Pink

n/A

Pink Carrier

n/n

Non-carrier

What can a breeding produce?

Knowing the DNA of both parents, we can estimate the probabilities of colors, Tan, Merle, Fluffy and carriers. These are probabilities per puppy, not a guarantee of the exact number that will appear in a litter.

Two Blue carriers

D/d × D/d

  • 25% D/D · non-carrier
  • 50% D/d · carrier
  • 25% d/d · visual Blue

Merle with non-merle

n/M × n/n

  • 50% n/M · Merle
  • 50% n/n · non-merle

Visual Fluffy with Fluffy Carrier

L1/L4 × L/L4

  • 50% Visual Fluffy
  • 50% Fluffy Carrier

Want to know what your female could produce with one of our studs?

Send us your female's DNA test and we will carry out a genetic evaluation of the breeding: potential colors, genetic probabilities, Fluffy and carriers, Merle, Tan and the possible combinations that could be passed on. We can also prepare an indicative visual representation of how some of the possible puppies could look according to the expected genetics.

Evaluate a breedingMeet our studs →

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