Pyruvate Kinase Deficiency in the Beagle: Why PKLR Testing Is Breed-Specific

SamMy vet says my Beagle’s anaemia keeps coming back, and someone online told me it might be genetic.
Elena MarshIt can be. A team at the University of Pennsylvania described a Beagle-specific pyruvate kinase mutation in 2012, in dogs referred from across the United States.
SamThen I just order a pyruvate kinase test and I have my answer?
Elena MarshThat is exactly where owners come unstuck. The canine mutations differ by breed — the OMIA database now records six of them — so a test built around another breed’s variant will report your Beagle as clear.
SamAnd if it did come back positive, how serious is this for a dog?
Elena MarshMore serious than the feline version. That same 2012 paper records osteosclerosis appearing from about a year of age, and the laboratories that run the test describe a sharply shortened life expectancy.

Bottom line: The Beagle has its own pyruvate kinase mutation — PKLR c.994G>A, p.(G332S), a missense change in exon 8 — and it is not the same variant that affects Labradors, Pugs, Basenjis or West Highland White Terriers. That single fact is the whole practical lesson: before you buy “a PK deficiency test,” confirm in writing that the laboratory reads the Beagle variant, because a panel built for another breed will hand you a clean result that means nothing. A DNA result is not a diagnosis. It tells you which copies of one gene a dog inherited; it cannot tell you why a particular dog is anaemic today, and it cannot replace a blood count, an examination and a veterinarian’s judgement. If your Beagle is pale, tires quickly or has been anaemic more than once, that is a veterinary appointment, not a swab kit.

The Beagle is a fixture of American dog life. It ranked seventh on the American Kennel Club’s list of the most popular breeds of 2025, unchanged from the year before, in a top ten led by the French Bulldog, Labrador Retriever and Golden Retriever. In Britain the breed is common enough to be studied on its own: a 2025 VetCompass analysis by O’Neill and colleagues at the Royal Veterinary College identified 19,906 Beagles among 2,250,417 dogs under primary veterinary care, or 0.88 per cent of the national caseload.

That British study is worth holding in mind while you read the rest of this article, because it is the closest thing we have to a picture of the ordinary Beagle. From a randomly sampled 3,729 of those Beagles — 18.73 per cent of the total — the disorders recorded most often were obesity (24.27 per cent), periodontal disease (17.78 per cent), overgrown nails, otitis externa and anal sac impaction; and across the 322 deaths recorded during the study period, the median age at death was 11.28 years. Inherited haemolytic anaemia does not appear anywhere near the top of that list. Pyruvate kinase deficiency is a real, documented, serious problem in this breed, and it is also a rare one. Both statements are true, and the numbers you will meet below only make sense if you hold them together.

What pyruvate kinase does, and what happens when a Beagle cannot make it

A red blood cell is a strange piece of biology: it carries oxygen for the rest of the body but has no mitochondria of its own, so it cannot burn that oxygen for its own energy. It runs entirely on glycolysis. Pyruvate kinase catalyses the last step of that pathway, and it is one of the two steps that actually yields ATP. Take the enzyme away and the cell is left short of energy, cannot maintain its membrane and its ion pumps, and is cleared from the circulation far earlier than the usual three or four months. The result is a chronic haemolytic anaemia, inherited — as the 2012 Pennsylvania paper states plainly — “as an autosomal recessive trait.” Two copies of the variant are needed for disease; one copy makes a clinically normal carrier.

The research history runs across three decades and four laboratories. Whitney and colleagues published the molecular basis of canine PK deficiency in Experimental Hematology in 1994, working in the Basenji, where the disease had long been recognised. Skelly, Wallace, Rajpurohit, Wang and Giger followed in the American Journal of Veterinary Research in 1999 with a six base pair insertion in exon 10 of West Highland White Terriers. Then in 2012 Inal Gultekin, Raj, Foureman, Lehman, Manhart, Abdulmalik and Giger reported three further mutations at once in the Journal of Veterinary Internal Medicine — one each in the Labrador Retriever, the Pug and the Beagle — and connected them to a syndrome of haemolytic anaemia, osteosclerosis and secondary haemochromatosis. The list is still growing: in December 2025, Ma, Kuo and Liu reported in Animals a novel truncating PKLR variant in a Miniature Schnauzer caused by exon skipping, which they describe as the first documented truncated PKLR protein in a dog.

SamWhy is it always red blood cells? Surely other cells need the same enzyme.
Elena MarshThey do, but they have mitochondria to fall back on. The red cell runs on glycolysis alone, which is why a PKLR fault shows up there first and hardest.

Why the Beagle is on the testing list at all

The Beagle earned its place on that list through the 2012 study. The Pennsylvania group screened 68 Beagles — and the composition of that group matters more than any percentage drawn from it. Of the 68, 39 were anaemic, 10 were submitted for genetic screening and 19 were submitted for unstated reasons. Within that group, 35 per cent were PK-deficient, 3 per cent were carriers, and the mutant allele frequency was 0.37.

Do not carry those numbers out of the room. The authors themselves wrote that “the dogs screened were highly biased toward anemic and related dogs” — these were animals sent to a referral genetics laboratory precisely because something was wrong with them, or because they were related to a dog for which something had been. The figures describe that sample and nothing else. They are not the prevalence of PK deficiency among Beagles in general, and anybody who tells you that a third of Beagles are affected has misread the paper. The VetCompass picture of nearly 20,000 British Beagles, where haematological disease does not feature among the common diagnoses, is the useful counterweight.

The variant itself is a single base change in exon 8 of PKLR: c.994G>A, replacing glycine with serine at codon 332. It is a missense mutation rather than a truncation, and the 2012 authors noted that the substituted glycine sits near the magnesium binding site and that the change was not tolerated by SIFT analysis — computational evidence, on top of the clinical picture, that this is the change doing the damage. In the PK-deficient Beagles of that series, the average age at diagnosis was two years, with a range from seven months to nine years.

SamSo the thirty-five per cent figure is basically meaningless for my dog?
Elena MarshIt is meaningful for the group it came from — anaemic and related dogs sent in for testing — and misleading for anyone else. The paper says so itself, in those words.

The part most owners get wrong: canine PK tests are breed-specific

In cats, a single PKLR variant accounts for the disease across many breeds, and one test covers them all. Dogs are not like that. Online Mendelian Inheritance in Animals now records six separate canine PKLR variants — in most cases one per breed, though the West Highland White Terrier and the Cairn Terrier share theirs — spread across several exons and of several different types: a frameshift deletion in the Basenji, an in-frame duplication in the West Highland White Terrier, a nonsense change in the Labrador Retriever, missense changes in the Pug and the Beagle, and the 2025 splicing variant in the Miniature Schnauzer. Nor does the exon number identify them: the Labrador and Pug variants both sit in exon 7, and the Beagle and Miniature Schnauzer variants both in exon 8. A laboratory assay designed to read one of these will not read the others. It will simply report “normal” for the variant it looked at, which is technically correct and practically useless.

You can see this written into the laboratories’ own catalogues. PennGen, the laboratory at the University of Pennsylvania School of Veterinary Medicine where much of this research was done, lists its canine PK deficiency test breed by breed with the exact variant beside each name — Beagle c.994G>A, Labrador Retriever c.799C>T, Pug c.848T>C, Basenji c.433delC, and c.1431_1432insAAGACC for both the West Highland White Terrier and the Cairn Terrier. LABOKLIN likewise publishes a defined breed list for its PK test: Australian Labradoodle (Cobberdog), Basenji, Beagle, Cairn Terrier, Labradoodle, Labrador Retriever, Pug and West Highland White Terrier. Consumer panels split the condition the same way — Embark’s public health library carries the PKLR exon 5 Basenji variant and the PKLR exon 7 Pug variant on separate pages, each naming its own breed.

The practical instruction follows directly. When you order, do not ask “do you test for PK deficiency?” Ask “does your test read PKLR c.994G>A, the Beagle variant?” and keep the answer. When you read a certificate for a puppy’s parents, look for the variant, not just the disease name. And treat a clear result as clear for that variant only: the Miniature Schnauzer case published in 2025 is a reminder that novel variants exist outside the panels, and that a dog can be PK-deficient while every commercial test says otherwise.

SamHow would I even know which variant a lab is looking at?
Elena MarshPennGen prints the mutation next to each breed on its test page, so you can check yours against it. If a laboratory will not tell you, that is an answer in itself.

What it looks like in a dog, and why the canine disease is the harsh one

What owners notice is vague at first: a dog that runs out of steam on walks it used to enjoy, gums and inner eyelids that look washed out rather than pink, sometimes a faster heartbeat or an abdomen that feels full because the spleen and liver have enlarged. The blood picture is more distinctive. In the three index dogs of the 2012 series the anaemia was “highly regenerative, macrocytic, and normo- to hypochromic,” with marked polychromasia and anisocytosis on the smear and reticulocyte counts far above the reference range — the bone marrow working flat out to replace cells that keep being destroyed.

Then comes the part that separates dogs from cats. Affected dogs develop a progressive myelofibrosis and osteosclerosis — bone laid down inside the marrow cavity, visible on radiographs of the femur or humerus as increased cortical bone and blotchy density where marrow should be. The 2012 paper records that “osteosclerosis develops at about 1 year of age and is progressive.” Alongside it, iron from the constant haemolysis accumulates in the liver; one necropsied dog in the series had a liver iron concentration of 37,300 ppm dry weight against a reference interval of 350–1,200, with bridging portal fibrosis. Laboklin’s UK description of the disease puts the contrast bluntly: the myelofibrosis, osteosclerosis and liver failure are associated with the disease “in dogs but not cats,” and are the major cause of death in affected dogs.

Within dogs, though, the outlook is not uniform, and the Beagle sits at the better end. The 2012 authors observed that PK-deficient West Highland White Terriers and Beagles “have been observed to live 9 years despite being persistently severely anemic,” whereas Basenjis and PK-deficient Labrador Retrievers “do not exceed 5 years of age, even with appropriate supportive treatment.” That is an observation the authors drew from earlier published case reports and expressly described as anecdotal, not a prognosis for any individual dog, and it is the kind of statement that belongs in a conversation with your own vet rather than in your own head. It would also be a mistake to read it as a mild disease. The laboratories that actually run the test describe the outlook bluntly: PennGen states that affected dogs “have a dramatically shortened life expectancy and are generally humanely euthanized around 2 years of age” and rates life expectancy as poor; Laboklin’s description says the life expectancy of affected dogs is shortened and most die before four years of age; and Wisdom Panel’s Beagle page says the disease leads to the death of the affected dog, “usually at less than 5 years of age.” The nine-year Beagles come from a handful of earlier case reports, not from the expectation for this disease.

One more thing, and it is the reason the clinical route matters as much as the genetic one. Juvet, Giger, Battersby, Menaut, Syme and Mooney reported three PK-deficient West Highland White Terriers in Ireland and the UK in the Irish Veterinary Journal in 2013, and all three had first been diagnosed and treated for immune-mediated haemolytic anaemia before genetic testing showed what was actually wrong. Their published conclusion was about their own breed and no other: that PK deficiency should be considered in anaemic West Highland White Terriers worldwide, particularly where evidence of an immune-mediated, infectious or toxic underlying cause is lacking. Extending that reasoning to any breed with a known PKLR variant, the Beagle included, is our inference and not theirs — but the diagnostic trap they documented is not a property of the West Highland White Terrier. Diagnosis starts with a physical examination and a complete blood count, proceeds by excluding infection, immune-mediated destruction and other causes, and only then is a DNA test the thing that names the cause. The sequence is not optional, and the DNA test is never the diagnosis on its own.

Transfusion support: the UK and the US are built differently

There is no cure for PK deficiency, and the supportive care an affected dog may need over a lifetime includes blood. That makes transfusion supply a practical question rather than a theoretical one, and it is the point where the two markets diverge most sharply — so it is worth knowing how your country works before a crisis rather than during one.

Britain runs a national charity for this. Pet Blood Bank UK, a registered charity, collects at donation sessions around the country, processes and stores the blood at its centre in Loughborough, Leicestershire, and says it operates “24 hours a day, seven days a week, to ensure blood is always available.” It is explicit that it deals with practices, not owners — “We can only accept calls from vets. If your pet needs blood, please ask your vet to contact us” — and products are supplied at cost price, with practices signing its terms agreeing to charge clients only what the charity charged them. The awkward corollary for this breed is on the donor side. Pet Blood Bank’s donor criteria require a dog to be between one and eight years old, to “weigh more than 25kg (55 pounds / 3 stone 13 pounds)” and to have a good temperament. The median adult bodyweight of a UK Beagle in the VetCompass study was 18.19 kg, with an interquartile range of 15.68 to 21.07 kg. A typical Beagle is therefore a plausible recipient and, on weight alone, not a possible donor — which is worth knowing if you had assumed your own dog or a friend’s could simply give blood in an emergency.

That is not quite the whole British picture, because the big referral hospitals also hold blood of their own. The Royal Veterinary College’s Queen Mother Hospital for Animals, on its Hawkshead campus at Hatfield in Hertfordshire, runs a Transfusion Medicine Service with a dedicated blood donor room and its own enrolled cat and dog donors, producing products for the clinicians working inside that hospital. The Queen’s Veterinary School Hospital in Cambridge similarly asks owners to register dogs and cats to boost its blood donor bank, alongside the small animal internal medicine service it takes referrals into. Both are reached through your own practice rather than directly, and that is the point to take away: in Britain the route to a transfusion runs through your first-opinion vet either way, whether the unit comes from Loughborough or from the referral hospital’s own fridge.

The United States has no single national equivalent. Supply runs on two parallel tracks: independent commercial blood banks that ship products to practices, and university veterinary teaching hospitals that operate their own in-house donor programmes and transfusion services. Blue Ridge Veterinary Blood Bank of Purcellville, Virginia — which describes itself as “the largest canine volunteer blood bank in the nation” — is a worked example of the first kind. It publishes its price list openly: packed red blood cells at $166 for a 125 ml DEA-positive unit and $271 for the negative equivalent, or $271 and $410 respectively for 250 ml. Its donor requirements ask that dogs be “at a healthy weight of at least 40lbs, between the ages of 1-7 years old.” Note that the 40 lb floor is about 18 kg, so where a typical Beagle falls short of the British donor threshold it sits right at the American one. The Canine Blood Donor Program at the University of Florida Small Animal Hospital in Gainesville is a worked example of the second kind, enrolling neutered dogs of one to five years and 40 pounds or more after a physical examination, blood tests and infectious disease screening, and holding a unit in reserve for each donor should that dog ever need one itself.

Geography is where this becomes personal, and it cuts the same way on both tracks. Blue Ridge’s own donation sites are clustered in a single corner of the map — twelve practices listed across Maryland and Virginia — even though it supplies hospitals nationwide, which means everywhere else is served by shipping rather than by a local vein. University donor programmes sit wherever the veterinary colleges happen to be, so an owner in a metropolitan area may have a teaching hospital within an hour’s drive while an owner three states away from the nearest one does not. None of that is a reason to panic; it is a reason to ask the question early. Put it to your own practice as two plain questions — which blood supplier do you use, and how long does a unit take to reach you — and ask them at a routine appointment rather than at two in the morning.

SamCould my own Beagle donate blood if another dog needed it?
Elena MarshIn Britain, almost certainly not — Pet Blood Bank wants donors over 25 kg, and the median UK Beagle is 18.19 kg. In the US the bar at one Virginia bank is 40 lb, so a well-grown Beagle can just reach it.

Where a Beagle owner can actually get this tested in the US and the UK

In the United States, the reference option is PennGen, where the Beagle variant was characterised. The canine PK deficiency test is listed at $75.00, and the laboratory accepts cheek brushes or swabs and fresh EDTA blood. One practical detail catches people out: the page states plainly that “We do not provide kits. Please collect the sample following the sample collection and shipping instructions before ordering a test.” There is no box in the post with everything in it. You — or your vet, if you are sending blood — assemble the sample yourself to the laboratory’s published instructions and pay the postage, so read those instructions before you order rather than after. The advantage is not price or convenience but specificity: you are ordering from the laboratory that publishes the Beagle mutation next to the Beagle’s name.

Consumer panels are the other route and are convenient if you want a broad screen of a pet rather than a breeding document. Wisdom Panel publishes a Beagle-specific pyruvate kinase deficiency page, describing a PKLR G>A variant on chromosome 7, juvenile onset from zero to two years, autosomal recessive inheritance, and signs including anaemia, pale mucous membranes, enlargement of the spleen and liver, osteosclerosis and myelofibrosis; its Premium kit is sold at around $159.99 and is advertised as covering more than 265 health tests. Its breeding advice is the standard one and worth repeating: a carrier can safely be bred to a clear dog, but carrier-to-carrier matings are not advised.

In the United Kingdom the choice is narrower than owners expect. Laboklin UK offers PK Deficiency at £48.00 including VAT with a two to three week turnaround, accepting either buccal swabs or 0.5–1 ml of whole blood in EDTA, and its breed list names the Beagle. Canine Genetic Testing at the University of Cambridge, which many British owners try first for terrier and hound DNA tests, returns no results at all for pyruvate kinase — a reminder that “my usual lab” and “a lab that runs this test” are not the same thing. Whichever you choose, the test is a once-in-a-lifetime one: a dog’s genotype does not change, so a single certificate stands for life.

SamIs the cheap consumer kit as good as the university lab for this?
Elena MarshFor a pet, often yes — Wisdom Panel publishes a Beagle-specific PK page. For a breeding certificate, ask the lab to confirm the variant in writing before you pay.

Breeders, the law, insurance and the referral route

Here is the gap that makes this article necessary. Neither country’s standard Beagle health panel includes PK deficiency. In the United States, the National Beagle Club of America’s screening tests page makes hip dysplasia evaluation, Musladin-Lueke Syndrome DNA testing, thyroid certification, cardiac certification and eye examination mandatory for a CHIC number, with Factor VII deficiency optional. Pyruvate kinase deficiency is described on the same page, and the club points owners to PennGen for it — but it is not part of the CHIC requirement. In Britain, the Royal Kennel Club’s Beagle breed page lists DNA tests for Lafora’s disease and neonatal cerebellar cortical degeneration as good practice, and Factor 7 deficiency, Imerslund-Gräsbeck syndrome and Musladin-Lueke syndrome as best practice. PK deficiency does not appear.

So a Beagle breeder can be doing everything both bodies ask and still have never run a PK test, entirely in good faith. If you are buying a puppy, that means you have to ask for it by name rather than assume a CHIC number or an Assured Breeder listing covers it — and then ask to see the actual certificates for both parents, check that the variant tested is the Beagle c.994G>A, and check that the dog identification on the certificate matches the microchip number you are being shown. If either parent is a carrier, ask what the other parent’s result was; a carrier bred to a clear dog cannot produce an affected puppy, and any honest breeder will say so without being pushed.

The law will not do that asking for you, and it is worth being precise about what it does instead. In England, breeding dogs is a licensable activity under The Animal Welfare (Licensing of Activities Involving Animals) (England) Regulations 2018 once a person is breeding three or more litters of puppies in any twelve-month period, or is breeding dogs and advertising a business of selling them. The licence conditions in Schedule 6 are genuinely useful to a buyer: a licence holder may not advertise or sell a dog that was not bred by them, or sell one anywhere other than the premises where it was born and reared; every advertisement must carry the licence number, name the issuing local authority and show a recognisable photograph and the dog’s age; no puppy under eight weeks may be sold or permanently separated from its mother; and a puppy “may only be shown to a prospective purchaser if it is together with its biological mother.” The 2020 change usually called Lucy’s Law is the 2019 amending instrument, made on 8 July 2019 and in force from 6 April 2020, which added “puppies or kittens which were not bred by the licence holder” to the list of animals a pet-selling licence holder may not sell — closing the third-party dealer route. What none of it does is require a test. Schedule 6 says no dog may be kept for breeding where it can reasonably be expected “on the basis of its genotype, phenotype or state of health” that breeding from it could harm the dog or its offspring — a genotype-aware standard with no testing obligation attached to it. The words “genetic,” “hereditary,” “DNA” and “health test” do not appear anywhere in the instrument.

The American federal picture is thinner still. Licensing under the Animal Welfare Act reaches commercial dealers, but 9 CFR § 2.1(a)(3) exempts retail pet stores and “any person who maintains a total of four or fewer breeding female pet animals… and sells only the offspring of these animals, which were born and raised on his or her premises, for pets or exhibition.” A retail pet store is in turn defined as a place where “the seller, buyer, and the animal available for sale are physically present so that every buyer may personally observe the animal prior to purchasing” — which is why face-to-face sales sit outside the licensing net while sight-unseen shipping does not. Most Beagle breeders a pet buyer meets will fall under that exemption entirely, and even a licensed one is inspected against standards for housing, exercise, feeding, watering, sanitation and veterinary care; the words “genetic” and “hereditary” appear nowhere in them. Where American buyers do have a statutory lever is at state level. New York’s General Business Law § 753 gives 14 business days where a veterinarian of the consumer’s choosing certifies the animal unfit because of illness, or of the presence of symptoms of a contagious or infectious disease, but one hundred and eighty calendar days for a congenital malformation, with remedies of refund, exchange or reimbursement of veterinary costs. California’s Health and Safety Code § 122100, within the article governing the sale of dogs by breeders, requires a written notice of rights and runs to one year for congenital or hereditary conditions, with refund, replacement, or keeping the dog plus veterinary reimbursement. Windows, covered conditions and proof requirements vary state by state, so check your own before you buy rather than after.

Put those two paragraphs together and the conclusion is uncomfortable but clear: no rule anywhere in either country obliges a breeder to test for PK deficiency, or to disclose a result if they have one. The only enforceable version of that duty is the one you write yourself — ask for “both parents tested for PKLR c.994G>A” to be stated in the sales contract, with the laboratory certificates attached to it, so that a silence later is a breach of something rather than merely a disappointment.

Insurance deserves a sentence of its own because the two markets work differently. AKC Pet Insurance sells hereditary and congenital condition cover in the United States as an expansion of a policy rather than as standard, subject to a 30-day waiting period. In the United Kingdom, Petplan includes conditions a pet has inherited or is predisposed to within its standard dog policy, and defines a pre-existing condition as one an owner has noticed previously or a vet has previously diagnosed. In both markets the same instruction follows: insure before signs appear, and read the hereditary clause rather than assuming it works in your favour. A DNA result you already hold is not in itself a claim, but symptoms you have already noticed almost certainly are.

If a result or a blood count does point this way, the route is your own veterinary practice first. American owners can be referred onward to a board-certified specialist in small animal internal medicine, a field the American College of Veterinary Internal Medicine lists as covering haematology and immunology; its public directory searches by state, city or postcode, and the college notes that a referral from a general practitioner is helpful but not strictly required. Do that search now rather than on the day you need it: find the nearest board-certified internal medicine specialist in your own state, write the practice name down, and you will have turned a frightening open question into a phone number. British owners go through their own practice, which can refer onward to an RCVS Specialist in Internal Medicine (Small Animal), or to a university veterinary teaching hospital — the Royal Veterinary College’s internal medicine service at the Queen Mother Hospital for Animals in Hatfield, whose team lists haematology among its special interests, and the internal medicine service at the Queen’s Veterinary School Hospital in Cambridge are two of them. The RCVS Find a Vet register is where you look up a veterinary surgeon and check whether a practice is RCVS-Accredited. There is no cure for PK deficiency; care is supportive, which is exactly why it is worth having the right clinician involved early.

It is fair to ask what the first step costs, and Britain gives you at least one published figure to anchor on. The university-run first-opinion practice at the Queen’s Veterinary School Hospital in Cambridge lists a consultation in normal working hours at £50, rising to £150 or £230 out of hours for registered patients. That is one practice’s published list rather than a national average, and blood work, imaging and any referral onwards are charged on top of it — but it gives an order of magnitude for the appointment at which a blood count actually gets requested, and it is the appointment that matters most, because it is the one that turns “my dog seems tired” into a number on a haematology report.

What to do next

• If your Beagle is pale, tires easily or has been anaemic more than once, book a veterinary appointment and a complete blood count before you buy any test kit.
• When ordering a PK test, ask the laboratory in writing whether it reads PKLR c.994G>A, the Beagle variant, and keep the reply.
• Treat a clear result as clear for that one variant — it does not rule out other causes of anaemia, and it does not rule out variants no panel yet covers.
• Take any result, clear or not, to your own vet before you act on it. A genotype is not a diagnosis.
• Before symptoms ever appear, ask your own practice two questions: which blood supplier it uses and how fast a unit arrives, and which internal medicine specialist or teaching hospital it refers to. Write both down.
• Look up the specialist yourself as well — in the US through the ACVIM directory for your own state, in the UK through your own practice or a university veterinary teaching hospital — and keep the name before you need it.
• If you order from PennGen, note that it does not supply collection kits: read its sample collection and shipping instructions and assemble the sample before you place the order.
• Buying a puppy: ask specifically for PK results on both parents, because neither the CHIC panel in the US nor the Royal Kennel Club’s Beagle list requires them — and no law in either country requires them either.
• Get “both parents tested for PKLR c.994G>A” written into the sales contract with the certificates attached, and in England check the breeder’s licence number and that you are meeting the puppy with its mother at the premises where it was bred.
• Never breed carrier to carrier; carrier to clear cannot produce an affected litter.
• Arrange insurance before any signs appear, and read how your policy handles hereditary conditions and waiting periods.
• Test once. A dog’s genotype does not change, so one certificate lasts a lifetime.

Frequently asked questions

Q. Does a positive DNA result mean my Beagle has pyruvate kinase deficiency?
It means your dog inherited two copies of the PKLR c.994G>A variant. That is a genetic finding, not a clinical diagnosis. Diagnosis rests on examination and blood work — a regenerative anaemia, an elevated reticulocyte count and the exclusion of infection and immune-mediated destruction — and belongs to your veterinarian, who should see the result rather than receive a summary of it by phone.

Q. My Beagle’s PK test came back clear. Can I stop worrying about anaemia?
No. A clear result rules out one variant in one gene. Anaemia in dogs has many causes, and the 2025 Miniature Schnauzer case shows that novel PKLR variants exist outside the panels that laboratories currently run. If your dog is pale or tiring easily, that needs a veterinary assessment regardless of what any DNA certificate says.

Q. A lab offers “PK deficiency testing” but will not say which variant. Is that good enough?
Not for a Beagle. Canine PKLR variants are breed-specific — OMIA records six, in different exons and of different types — so a test built for the Labrador, Pug or West Highland White Terrier variant will read a PK-deficient Beagle as clear. PennGen publishes the mutation alongside each breed on its test page, which gives you something concrete to compare an answer against.

Q. Is a third of the breed really affected?
No, and this is the most commonly misquoted figure on the subject. The 35 per cent came from 68 Beagles submitted to a referral genetics laboratory, of which 39 were already anaemic and 19 were sent for unstated reasons. The authors stated that their sample was heavily biased toward anaemic and related dogs. It describes that group only, and says nothing about the general Beagle population.

Q. My Beagle is a carrier. Does that affect his health?
Carriers of this autosomal recessive condition have one normal copy and one variant copy, and are not expected to show clinical signs. The consequence is for breeding: a carrier bred to a clear dog cannot produce an affected puppy, while carrier-to-carrier matings are not advised. Discuss the specific result with your veterinarian, and share it with anyone considering your dog for breeding.

References

• Inal Gultekin G, Raj K, Foureman P, Lehman S, Manhart K, Abdulmalik O, Giger U (2012). “Erythrocytic Pyruvate Kinase Mutations Causing Hemolytic Anemia, Osteosclerosis, and Secondary Hemochromatosis in Dogs.” Journal of Veterinary Internal Medicine 26(4):935-944.
• Skelly BJ, Wallace M, Rajpurohit YR, Wang P, Giger U (1999). “Identification of a 6 base pair insertion in West Highland White Terriers with erythrocyte pyruvate kinase deficiency.” American Journal of Veterinary Research 60(9):1169-1172.
• Whitney KM, Goodman SA, Bailey EM, Lothrop CD Jr (1994). “The molecular basis of canine pyruvate kinase deficiency.” Experimental Hematology 22(9):866-874. PMID 7520391.
• Ma TY, Kuo CJ, Liu PC (2025). “From Mutation to Manifestation: Evaluation of a PKLR Gene Truncation Caused by Exon Skipping in a Schnauzer Terrier.” Animals 15(24):3634.
• Juvet F, Giger U, Battersby I, Menaut P, Syme HM, Mooney CT (2013). “Erythrocyte pyruvate kinase deficiency in three West Highland white terriers in Ireland and the UK.” Irish Veterinary Journal 66(1):12.
• O’Neill DG, Schiksnis MR, Brodbelt DC, Church DB, Goldberg S, Engdahl KS (2025). “Beagles kept as companion animals in the UK – demography, disorders and mortality.” Companion Animal Health and Genetics 12(1):1.
• Online Mendelian Inheritance in Animals. OMIA:000844-9615, “Pyruvate kinase deficiency of erythrocytes in Canis lupus familiaris (dog)” – the list of canine PKLR variants by breed.
• PennGen, University of Pennsylvania School of Veterinary Medicine. “PK Deficiency” test – breed-by-breed variant list, $75.00, cheek swab or EDTA blood.
• LABOKLIN. “Pyruvate kinase deficiency (PK)” – breed list and autosomal recessive inheritance.
• Laboklin UK. “PK Deficiency (Pyruvate Kinase Deficiency)” – £48.00 incl. VAT, 2-3 weeks, buccal swab or 0.5-1 ml EDTA blood, breed list including the Beagle.
• Wisdom Panel. “Pyruvate Kinase Deficiency (PKD)” in Beagles – PKLR, juvenile onset, signs and breeding guidance.
• Embark Vet. “Pyruvate Kinase Deficiency, PKLR Exon 5, Basenji Variant” – one variant per page, autosomal recessive.
• Embark Vet. “Pyruvate Kinase Deficiency, PKLR Exon 7, Pug Variant” – the separate Pug entry.
• The National Beagle Club of America. “Screening Tests” – CHIC-mandatory tests and pyruvate kinase deficiency via PennGen.
• The Royal Kennel Club. “Beagle” breed page – good practice and best practice DNA tests and health schemes.
• American Kennel Club. “The Most Popular Dog Breeds of 2025” – the Beagle at seventh.
• AKC Pet Insurance. “Hereditary & Congenital Conditions Coverage” – optional cover, 30-day waiting period.
• Petplan UK. “Dog Insurance” – inherited and congenital conditions within the standard policy; definition of a pre-existing condition.
• American College of Veterinary Internal Medicine. “Small Animal Internal Medicine” – specialist finder and scope including haematology.
• Royal College of Veterinary Surgeons. “Find a Vet” – register of veterinary surgeons and RCVS-Accredited Practices.
• Pet Blood Bank UK. “Can your dog donate blood?” – canine donor criteria: one to eight years old, more than 25 kg, good temperament.
• Pet Blood Bank UK. “Order blood products” – supply to veterinary practices only, at cost price, from the Loughborough centre.
• Royal Veterinary College. “Transfusion Medicine Service” – in-house blood donor room and blood products at the Queen Mother Hospital for Animals.
• The Queen’s Veterinary School Hospital, University of Cambridge. “General Practice Price List” – £50 consultation in normal working hours.
• Blue Ridge Veterinary Blood Bank. “Blood bank product pricing” – canine packed red blood cell prices by volume and DEA 1 type.
• University of Florida Small Animal Hospital. “Canine Blood Donor Program” – eligibility, screening and donor benefits.
• The Animal Welfare (Licensing of Activities Involving Animals) (England) Regulations 2018, Schedule 6 – specific licence conditions for breeding dogs.
• The Animal Welfare (Licensing of Activities Involving Animals) (England) (Amendment) Regulations 2019 – “Lucy’s Law,” made 8 July 2019, in force 6 April 2020.
• 9 CFR § 2.1 – Animal Welfare Act licensing requirements and exemptions, including the four-or-fewer breeding females exemption.
• New York General Business Law § 753 – 14 business days for illness, 180 calendar days for congenital malformation, and the consumer’s three remedies.
• California Health and Safety Code § 122100 – written notice of rights on the sale of dogs by breeders; one year for congenital or hereditary conditions.

Photo: Slyronit, CC BY-SA 4.0, via Wikimedia Commons.

About the author

Elena Marsh

Editor & writer (not a veterinarian)

A writer with a molecular-biology background and a lifelong dog and cat owner. Not a veterinarian — she translates peer-reviewed genetics research and primary data into plain language, always as information rather than diagnosis.