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Merle French Bulldog Health Problems

Merle French Bulldog: The unusual Frenchie

By: AuthorJackie Castle

Posted onPublished: August 24, 2021 - Last updated: July 11, 2022

CategoriesDog breeds

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The Merle French Bulldog or also known as the Blue Merle French Bulldogs is a stunning dog. But, we can’t only focus on that. The truth is, there is so much wrong with this mix.

In this article you will why you shouldn’t buy one. I will also explain where the merle gene comes from. And lastly, you will learn more about their health issues. And there are many!

Merle French Bulldog

We’ve mentioned the blue Merle French Bulldog, but that blue color isn’t a sky blue shade. It’s actually a grey color with a blue hue to it. This means that blue Frenchies are actually gray-ish Frenchies.

But, besides blue, the merle coat comes in other shades too, for example, black merle.

Merle is a French Bulldog coat hereditary pattern that dilutes random areas of the coat to a lighter color while leaving patches of the original color. When a French Bulldog has the “M” Merle allele and a negative “m” copy of the Merle allele, it gets this condition. (M/m) is a Merle French Bulldog.

When two French Bulldogs who are both carriers of (M/m) are bred together, there is a 25% chance that each youngster will be homozygous (M/M) for the merle trait. (M/M) carriers, commonly known as double merle, have a high rate of vision and hearing issues.

The Merle is sadly not purebred, and they are also not recognized by the American Kennel Club (AKC).

What does a Merle Frenchie look like?

Merles have a speckled pattern on their coat, uneven skin pigmentation on their nose and paws, and blue or odd-colored eyes. Blue merle and red merle are the two most common merle coat colors.

The merle gene not only affects the coat color, but it also changes the dark pigment in the eyes of French Bulldogs, turning them partially or completely blue or odd-colored. When it comes to skin color, the merle gene can turn the paws and noses of French Bulldogs pale pink.

Despite their alluring appearance, potential Merle French Bulldog owners should be warned that they are the consequence of improper breeding techniques and are prone to hearing problems and blindness.

What is a double Merle French Bulldog?

French Bulldog with two copies of the dominant “M” allele is known as a Double Merle (M/M). They are affected by ocular defeats and deafness, and are a result of poor breeding techniques. These dogs are also known as ‘fatal whites,’ because to their lack of color in their coat.

Double merle dogs are a problem topic for many breeders worldwide. French Bulldogs have sparked a lot of debate, with many official organizations refusing to register pups that are the result of merle-to-merle breeding.

Is the Merle French Bulldog purebred?

Because the merle gene does not naturally appear in this breed, Merle French Bulldogs are not purebred. Merle French Bulldogs are the consequence of selective breeding, and are produced by mating a French Bulldog with a merle-carrying dog, such as a Chihuahua. The American Kennel Club does not recognize the merle French Bulldog as a pure breed.

Merle double (M/M) Merle will always be passed down to the puppies of French Bulldogs, hence they should not be bred together. Responsible breeders should match a Merle (M/m) French Bulldog with a non-Merle (m/m) French Bulldog to generate merle offspring. Merles will make up roughly half of the litter, and there will be no Double Merles.

Merle gene

Everyone agrees that Merle Frenchies are beautiful. Their merle pattern is unique and will make everyone stop and stare. But do you know where the merle gene comes from?

This gene is not usual in Frenchies. To get the merle gene Frenchies to have to be bred with dogs that have the gene. For example, a Chihuahua. The point is to breed regular Frenchies with merle Chihuahuas.

Even if you breed a Merle Frenchie and a normal Frenchie, the puppies can’t be considered purebreds because the parents aren’t purebreds. I know this is a bit confusing. But that is one of the reasons why the AKC doesn’t accept them.

We also have to mention double merles or double merle French Bulldogs. There are many irresponsible French Bulldog breeders who only go for the money. Now, the merle coat is becoming more and more popular. And breeders know that.

So, they will do anything to get as many merle Frenchies. Some breeders might even try to pair two Merle French Bulldogs, which comes with a serious risk. With double merles, 25% of the puppies have a serious chance of being double merles.

Sadly, this can result in substantial removal of pigment, which can negatively affect sight and hearing. Double merles are almost white, they have blue eyes and very often are born with eye deformities and other serious health problems.

Color variations of the Merle French Bulldog

Did you know that there are three color versions of merles? Other hues of merles exist depending on the dominant gene that is diluted. Because they are rare French Bulldogs, the colors Black, Blue, and Lilac are three of the most sought after.

Merle Black

When the dominant gene in a French Bulldog is black, the dog is known as a Black Merle French Bulldog. The other coat colors are pushed out as a result of this. The dominant gene comes through in the three Frenchie hues black, tan, and fawn, giving the Black Merle its color and moniker.


Merle Lilac

The Lilac Merle French Bulldog is the rarest of the French Bulldogs, making them the most difficult to find. The Lilac hue is essentially a mix of chocolate and blue base coat colors. The blue tint is diluted once more, allowing the lilac color to shine through. The Lilac Merle also has light-colored eyes that last throughout their lives and are the color that is most likely to cause health problems.

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Merle Blue

The Blue Merle French Bulldog is commonly referred to as a blue-gene dog breed, however they are actually black Frenchies with a little diluted base color, giving their hair a blue tinge. Blue Merle French Bulldogs have a unique look to their eyes. They can keep their vivid blue eyes from puppyhood through adulthood and then have lighter eye colors than regular French Bulldogs.

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Health issues

Sadly, the merle gene doesn’t only make the dogs look different. There are a lot of health issues that come with this gene. This gene can cause hearing, sight, and blue eye defects.

To add to that, if you mix two Merle Frenchies it will even be worse. There is actually a 86% chance of those dogs being deformed, deaf or blind!

They can even have neurological defects, immune disorders, and extensive allergies. In the worst case, those poor puppies die!

Do you think this is worth it? I think not. No matter how pretty they are, it’s not worth it. I am sure you would rather have a healthy dog.

I don’t think you’re a bad person if you have one of these dogs. But, the fact is it’s not really okay.

Lastly, I want to add that the Merle French Bulldog has the shortest lifespan.

If there are no health difficulties or other complications, a Merle French Bulldog can expect to live for about ten years. Nonetheless, merle French Bulldogs are predisposed to visual and hearing problems, especially in double merles, due to their hereditary propensity.

A Merle French Bulldog’s lifespan is influenced by factors such as exercise and food.

Eye defects

I mentioned above that Merle Frenchie has a lot of eye issues. I want to go into more depth on that.

Merles have blue eyes. That is if they are even born with eyes. I know this sounds scary, but it’s the truth. Now, this isn’t only a problem in these dogs. Generally speaking, dogs with light colored eyes are more prone to having severe eye problems. Dogs that have light eye colors, like blue, tend to lose their sight very early in their life, compared to dogs with darker eye colors.

Missing an eye

French Bulldog breeders can’t promise you a healthy dog. They have no idea how the litter will be. There is a big chance some of the puppies are born without an eye. Or even without both eyes!

Sometimes the puppies will even have eyes. But they will be so deep in the socket that you can’t even see them!

Wandering eye

The wandering eye is an eye misalignment in which the eyes drift out.


Starburst Pupil

This is something like an eye cleft. Cataracts can also happen. This condition is the most dangerous, It’s also deadly.

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