French Bulldog & Pug DNA Testing and Health Genetics
DNA testing is an important part of how to understand breeding French Bulldogs & Pugs. DNA results help us identify inherited disease risks, colour and coat traits, carrier status, parentage, genetic diversity and how different dogs may complement each other in a breeding programme.
DNA testing is not used in isolation. A clear DNA profile does not automatically make a dog suitable for breeding. You also consider breathing, structure, movement, patellas, temperament, fertility, whelping history, veterinary feedback, family history and the long-term health of the line.
Why DNA Testing Matters
French Bulldogs and Pugs are a specialist breeds, and responsible breeding decisions should be based on more than appearance, colour or pedigree alone. DNA testing gives us another layer of information about each breeding dog, helping us understand inherited disease risks, carrier status, coat and colour traits, parentage, genetic diversity and how different dogs may complement each other in a breeding programme.
DNA testing helps us make more informed decisions before planning a mating. It allows us to identify traits that may not be visible by looking at the dog, including recessive genes that can be carried silently from one generation to the next. This is especially important when working with French Bulldogs, where health, breathing, structure, temperament and long-term soundness must remain more important than producing any particular colour.
What DNA Testing Can Tell Us
DNA testing can reveal information that is not always visible from appearance alone. A French Bulldog may look healthy, well-structured and typical for the breed, while still carrying recessive traits that could matter in future breeding plans. Testing helps us identify those hidden traits before making pairing decisions.
Depending on the test panel used, DNA results may provide information about inherited disease risks, carrier status, coat colour, coat type, parentage markers and genetic diversity. This can help us understand what a dog expresses, what it carries, and how it may complement or conflict with another dog in a planned mating.
One of the most important uses of DNA testing is identifying carrier status. A carrier dog is not necessarily unhealthy and should not automatically be considered unsuitable for breeding. However, carrier status must be managed responsibly. If two dogs carry the same recessive condition, there may be a risk of producing affected puppies. DNA testing helps breeders avoid those preventable pairings.
DNA testing also helps us understand colour and coat traits, including genes linked to blue, chocolate, cocoa, rojo, lilac, Isabella, tan point, brindle, pied and fluffy coat. These results are useful for planning, but they are secondary to health, temperament, structure and suitability.
For us, DNA testing is not about chasing colour. It is about having better information, reducing avoidable risk, and making more responsible decisions for the long-term strength of our breeding programme.
What DNA Testing Cannot Tell Us
DNA testing is valuable, but it does not tell the whole story of a dog. A DNA profile may show inherited disease results, carrier status, colour traits, coat traits and genetic diversity information, but it cannot fully assess the living dog in front of us.
A dog can have excellent DNA results and still be unsuitable for breeding if it has poor breathing, weak structure, unsound movement, poor temperament, reproductive issues or health concerns that are not covered by the DNA panel. In French Bulldogs, this distinction is especially important because many of the traits that matter most are not controlled by one simple gene.
Breathing quality, airway function, spinal soundness, skin resilience, movement, fertility, whelping ability, temperament and overall durability are influenced by a mixture of genetics, structure, environment and individual development. These traits require physical assessment, veterinary input, observation over time and honest breeder judgement.
For this reason, you should treat DNA testing as one part of a robust health and breeding programme. It helps reduce avoidable genetic risk, but it does not replace hands-on veterinary assessment, respiratory evaluation, patella checks, movement assessment, temperament evaluation or long-term knowledge of your lines.
Health DNA Testing and Inherited Disease Screening
Health DNA testing helps identify whether a dog carries specific inherited disease variants that are known and testable. Depending on the laboratory and panel used, results are usually reported in plain categories such as clear, carrier or affected.
A clear result generally means the dog does not have the tested variant for that condition. A carrier result means the dog has one copy of the variant but is not usually affected by that recessive condition. An affected result means the dog has inherited the relevant variant in a way that may place it at risk of developing, or being affected by, the condition tested for.
Carrier status is often misunderstood. A carrier dog is not automatically unhealthy, and being a carrier does not automatically remove a dog from a responsible breeding programme. What matters is how that information is used. If a dog carries a recessive condition, it should not be paired with another dog carrying the same condition, because that may create a risk of affected puppies.
Inherited disease screening helps make more informed decisions when selecting and pairing breeding dogs. It allows us to reduce avoidable genetic risk while still considering the whole dog, including breathing, structure, movement, temperament, fertility, whelping history, family history and veterinary feedback.
Colour DNA Testing vs Health DNA Testing
Not all DNA testing is the same. In dog breeding, DNA testing may be used for different purposes, including inherited disease screening, colour and coat testing, parentage verification and genetic diversity information.
Health DNA testing looks for specific inherited disease variants that may affect a dog’s health or may be passed on to future puppies. These results help breeders understand whether a dog is clear, a carrier or affected for particular testable conditions, and whether a planned pairing could create avoidable risk.
Colour DNA testing looks at genes connected with coat colour and coat type. In French Bulldogs, this may include traits such as blue, chocolate, cocoa, rojo, lilac, Isabella, tan point, brindle, pied, merle and fluffy coat. Colour DNA testing can be useful for understanding what a dog expresses and carries, but it should not be confused with health testing.
A dog may have a very interesting colour profile and still be unsuitable for breeding. Equally, a dog may have a simple or common colour and be extremely valuable from a health, temperament, structure and genetic-diversity point of view.
While you should consider both health genetics and colour genetics, they do not carry the same weight. Health, breathing, structure, temperament and long-term soundness come first. Colour testing helps understand and plan, but it does not override the wider health and suitability of the dog.
Genetic Diversity, Inbreeding and Breeding Decisions
DNA testing can also help breeders think about genetic diversity. Genetic diversity matters because a breeding programme should not only focus on avoiding known inherited disease variants. It should also consider how closely related dogs are, how much genetic variety is being preserved, and whether repeated use of similar lines may narrow the gene pool over time.
In dog breeding, this is often discussed through concepts such as heterozygosity, genetic diversity and coefficient of inbreeding. These tools do not make breeding decisions on their own, but they can help breeders understand whether a planned mating is likely to increase or reduce genetic variety.
A dog is not selected for breeding only because it has a rare colour, a fashionable pedigree or a clear result on one test. We look at the wider picture, including DNA results, health screening, breathing, structure, movement, temperament, fertility, whelping history, family history and how that dog may complement another dog.
Genetic diversity does not mean breeding randomly or ignoring type. It means making thoughtful choices so that health, temperament, structure and breed quality can be protected while avoiding unnecessary genetic narrowing. For a specialist breed such as French Bulldogs or pugs, this is an important part of long-term responsible breeding.
DNA Profile Examples From Our Programme
We believe DNA testing should be more than a phrase on a website. Where appropriate, we may publish redacted examples of DNA profiles from dogs in our breeding programme to help buyers understand the type of information we use when making breeding decisions.
These examples are provided for education and transparency. Personal details, microchip numbers, laboratory reference numbers, QR codes, account details and other identifying information may be removed before publication. The purpose is not to compare one dog against another, but to show how DNA results can help inform responsible breeding choices.
A DNA profile may show whether a dog is clear, a carrier or affected for particular inherited conditions, depending on the test. It may also show colour traits, coat traits, parentage markers and genetic diversity information. These results help us understand what each dog expresses, what each dog carries, and how that information should be considered when planning future pairings.
When we review a DNA profile, we do not look at one result in isolation. A carrier result, colour result or diversity score is interpreted alongside the whole dog, including health, breathing, structure, movement, temperament, fertility, whelping history, veterinary feedback and long-term knowledge of the line.
How We Use DNA Results When Planning Pairings
When planning a mating, DNA results help us understand how two dogs may work together genetically. We look at what each dog expresses, what each dog carries, and whether the pairing creates any avoidable risk.
For inherited disease screening, the most important question is whether both dogs carry the same recessive condition. A carrier dog can still be a valuable breeding dog, but it must be paired responsibly. DNA testing helps us avoid combinations that may produce affected puppies.
For colour and coat traits, DNA results help us understand what colours or coat types may be possible in a litter. This is useful for planning, but it does not decide the pairing on its own. A colour outcome may be interesting, but the overall quality and suitability of the dogs matters more.
For genetic diversity, DNA information can help us avoid repeatedly narrowing the gene pool. This is especially useful when working with specialised lines, rare colours or imported genetics, where it is easy for breeders to overuse the same related dogs.
In practice, DNA testing gives us a clearer map before we make a breeding decision. It helps us reduce guesswork, manage risk and plan pairings more carefully.
How to Read Our DNA Profile Examples
A DNA profile can look technical at first glance, but most of the information is easier to understand when it is broken into categories.
Health results usually show whether a dog is clear, a carrier or affected for specific testable conditions. A clear result means the tested variant was not detected. A carrier result means the dog carries one copy of a recessive variant. An affected result means the dog has the genetic result associated with being affected by, or at increased risk for, that condition.
Colour and coat results explain what the dog expresses and what it may carry. These results may include genes linked to fawn, tan point, recessive black, blue, chocolate, cocoa, rojo, lilac, Isabella, brindle, pied, merle or fluffy coat.
Genetic diversity results, where available, help show how genetically varied a dog is. These results are useful when thinking about long-term breeding decisions, but they are only one part of the wider picture.
When we publish redacted examples, the aim is to show how DNA information is interpreted in practice. The value is not in any one result by itself, but in how the whole profile helps inform responsible breeding decisions.
Redacted DNA Profile Examples From Our Programme
The following examples show the type of DNA information we use when assessing and planning breeding dogs at Le Epitome Kennels. These are redacted examples, with private details, microchip numbers, barcodes, registration details and laboratory reference information removed.
Each profile should be read as an example of how DNA testing supports breeding decisions. A DNA report is not a complete assessment of the dog, but it gives useful information about inherited disease status, carrier status, colour traits, coat traits and genetic diversity.
Example 1 — Health DNA Profile: French Bulldog Female - Retired
This redacted Orivet health certificate shows a French Bulldog female tested for several inherited conditions. With one copy of Degenerative Myelopathy(DM) which makes her a carrier.
Health genetics shown:
Clear / normal for:
Cone-Rod Dystrophy I - PRA
Hereditary Cataract
Hyperuricosuria
Multifocal Retinopathy CMR1
Carrier for:
Degenerative Myelopathy
This example shows why DNA testing is useful in a responsible breeding programme. It is useful because it shows why the carrier status must be understood properly. A carrier dog is not automatically unhealthy. The key breeding question is whether the dog is paired responsibly so that affected puppies are not produced. The result was identified before breeding decisions were made, which meant she could be paired with a non-carrier and the risk of producing affected puppies could be avoided.
She is now retired from our breeding programme, and her retained replacement offspring have been DNA tested and are not carriers for this condition. This is exactly how DNA testing should be used: not to label a carrier dog as unhealthy, but to make informed pairing decisions and improve the next generation.
Example 2 — Isabella & Tan Colour DNA Profile: French Bulldog Male
This redacted Animal Genetics report shows a French Bulldog male with an Isabella and tan phenotype with no tested heretible diseases present.
Colour and coat genetics shown:
A locus:
At/At — two copies of tan point
B locus:
b/b — two copies of testable chocolate / brown
Cocoa:
n/co — carries one copy of cocoa
D locus:
d/d — two copies of dilution
E locus:
EM/EM — two copies of melanistic mask
E/E — does not carry recessive yellow/cream
K locus:
n/n — negative for dominant black
Spotting:
N/N — negative for MITF-associated white spotting
Coat length:
L/L — short coat, does not carry long coat on the tested marker
Health results shown:
Clear for CMR1
Clear for cord1-PRA
Clear for Degenerative Myelopathy
Clear for Hyperuricosuria
Clear for Hereditary Cataract
CDDY and CDPA not tested on this report
This is a useful example of a layered colour profile. The Isabella and tan description is not one single gene. It is built from tan point, testable chocolate, dilution and other coat-colour results working together.
Example 3 — Lilac Fawn Colour and Fluffy Carrier Profile: French Bulldog Male
This redacted Animal Genetics report shows a French Bulldog male with a lilac fawn phenotype and no tested heretible diseases.
Colour and coat genetics shown:
A locus:
Ay/at — fawn/sable and carries tan point
B locus:
B/b — carries one copy of testable chocolate / brown
Cocoa:
co/co — two copies of cocoa
D locus:
d/d — two copies of dilution
E locus:
EM/E — one copy of melanistic mask
not recessive yellow/cream on this result
K locus:
n/n — negative for dominant black
Spotting:
n/n — negative for white spotting
Hair length:
L/l¹ — carries one copy of long coat / fluffy
This is a useful example because it shows how a dog can be visually short-coated while still carrying fluffy genetics. It also shows how colour descriptions such as lilac fawn can involve several interacting loci, including A locus, cocoa, dilution and mask.
Example 4 — Blue / Dilute and Fluffy Carrier Profile: French Bulldog Female
This redacted Animal Genetics report shows a French Bulldog female with a blue brindle phenotype but actually she was a lilac brindle as they missed the cocoa. No tested heretible diseases were found.
Colour and coat genetics shown:
A locus:
Ay/Ay — two copies of fawn/sable
B locus:
B/B — does not carry testable chocolate / brown
Cocoa:
No result obtained on this report
D locus:
d/d — two copies of dilution
E locus:
n/EM — one copy of melanistic mask
E/E — does not carry recessive yellow/cream
K locus:
n/KB — one copy of dominant black on this report
Spotting:
N/N — negative for MITF-associated white spotting
Hair length:
L/l — carries one copy of long coat / fluffy
Health results shown:
Clear for CMR1
Clear for cord1-PRA
Clear for Degenerative Myelopathy
Clear for Hyperuricosuria
Clear for Hereditary Cataract
CDDY and CDPA not tested on this report
This is a useful example of an older-style report where some information is complete and some is limited. The dilution result helps explain the blue coat description, while the hair length result shows fluffy carrier status. The cocoa result could not be interpreted because the laboratory was unable to obtain a result from the sample.
Genetic Conditions We Screen For and How We Manage Risk
The conditions listed below are examples of inherited disorders that may appear on French Bulldog DNA health panels or in the redacted DNA reports shown on this page. Not every laboratory tests for the same conditions, and not every report includes every test as some tests are new.
Cone-Rod Dystrophy / Progressive Retinal Atrophy
Cone-Rod Dystrophy is a form of Progressive Retinal Atrophy, often shortened to PRA. It affects the retina at the back of the eye, where light is processed for vision. In affected dogs, retinal cells can degenerate over time, leading to signs of retinal disease or progressive vision loss.
In DNA testing, this condition may appear under names such as cord1-PRA, crd4/cord1, Cone-Rod Dystrophy or RPGRIP1, depending on the laboratory.
How we manage it:
We use DNA results to identify whether a dog is clear, a carrier or genetically at risk. If a dog is a carrier, it should only be paired with a clear/non-carrier dog for that condition so affected puppies are not produced.
Degenerative Myelopathy
Degenerative Myelopathy, often shortened to DM, is associated with degeneration of the spinal cord. It is usually discussed as an adult-onset neurological condition that can affect hind-leg coordination and may progress over time.
The common DNA test looks at a variant in the SOD1 gene. A carrier dog is not expected to develop DM from one copy of this variant alone, but two copies may place a dog at increased genetic risk.
How we manage it:
Carrier status is recorded and used when planning pairings. A DM carrier can still be bred responsibly, but should be paired with a clear/non-carrier dog so puppies are not produced with two copies of the risk variant.
Hereditary Cataract
Hereditary Cataract testing looks for inherited variants associated with cataract development. Cataracts cause clouding of the lens of the eye and can interfere with vision. In some inherited forms, cataracts can develop young and may progress.
In French Bulldogs, hereditary cataract testing is commonly associated with the HSF4 gene on DNA reports.
How we manage it:
We use DNA screening to identify clear, carrier or affected results where this test is included. Dogs carrying a recessive cataract variant should be paired only with a clear/non-carrier dog for that condition.
Hyperuricosuria
Hyperuricosuria, often shortened to HUU, affects how uric acid is processed and excreted. Affected dogs can have elevated uric acid in the urine, which may increase the risk of urate bladder or kidney stones.
This condition is commonly associated with the SLC2A9 gene and is inherited in a recessive manner.
How we manage it:
DNA testing helps identify clear, carrier and affected results. A carrier dog is not expected to show disease from one copy of the variant alone, but carrier-to-carrier pairings should be avoided so affected puppies are not produced.
Canine Multifocal Retinopathy CMR1
Canine Multifocal Retinopathy 1, often shortened to CMR1, is an inherited eye condition associated with the BEST1 gene. It can cause areas of retinal change or small retinal detachments, sometimes described as blister-like lesions in the retina. It is usually detected young and does not always lead to blindness, but it is still important information for breeding.
How we manage it:
We record CMR1 status and avoid pairings that could produce affected puppies. As with other recessive conditions, a carrier dog can be used responsibly if paired with a clear/non-carrier dog.
CDDY / CDPA and IVDD-Related Screening
Some DNA panels may include CDDY and CDPA testing. These relate to FGF4 retrogene variants associated with short-legged structure and, in the case of CDDY, increased susceptibility to premature intervertebral disc degeneration and IVDD risk.
This area needs careful interpretation. A DNA result can provide useful information, but it does not replace physical structure assessment, movement assessment, veterinary advice or long-term observation. Spine and mobility health are not reduced to one DNA result.
How we manage it:
Where CDDY/CDPA results are available, they are considered as part of the wider picture. We do not treat one marker as a complete prediction of spinal health, but we do use the information to help make better breeding and veterinary-management decisions.
Our Practical Approach
Our aim is not simply to collect DNA certificates. The value is in how the results are used.
In practice, we:
record inherited disease results for breeding dogs
distinguish between clear, carrier and affected results
avoid carrier-to-carrier pairings for the same recessive condition
use clear/non-carrier pairings to manage carrier lines responsibly
retain and assess replacement offspring where they improve the next generation
keep DNA results in context rather than treating them as the whole health picture
A good example is a carrier result identified before breeding. Because the result was known, the dog could be paired with a non-carrier and the risk of affected puppies could be avoided. The retained replacement offspring have since been DNA tested and are not carriers for that condition. This is how DNA testing should be used: to make better decisions over time, not to label a carrier dog as unhealthy.
Newer and Emerging Tests We Monitor
Genetic testing changes over time. Some older DNA reports do not include tests that are now available, or may show certain items as “not tested” because they were not part of that laboratory’s panel at the time.
For this reason, we treat DNA testing as an ongoing part of our breeding programme rather than a one-off certificate. When new tests become available and are relevant to French Bulldogs, we review whether they should be added to our testing and breeding records.
Examples of newer or additional areas we monitor include CDDY/CDPA and IVDD-related screening, Cystinuria Type 3, airway-risk markers such as ADAMTS3, and other breed-relevant tests as laboratories update their panels. We also recognise that not every important health issue has a simple DNA test, which is why respiratory assessment, patella checks, movement, structure, cardiac health, eye health and veterinary assessment remain important.
A “not tested” result on an older DNA profile should not be read as a negative result. It simply means that particular test was not performed on that report. Where a test becomes relevant to future breeding decisions, we can update testing or use other forms of assessment before making breeding plans.
DVL2, Screw Tail and Spine-Related Awareness
Some French Bulldog DNA panels may include DVL2 testing. DVL2 is associated with the screw-tail phenotype seen in breeds such as French Bulldogs, Bulldogs and Boston Terriers. It is also discussed in relation to caudal vertebral changes and wider spine-awareness in these breeds.
This result needs careful interpretation. A DVL2 result should not be treated as a simple guarantee that a dog will or will not develop clinical spinal disease. In French Bulldogs, it is better understood as one breed-relevant marker that should be considered alongside the dog’s movement, comfort, structure, veterinary assessment and long-term observation.