TheDogPlace.org - Global Canine Communication

 

Canine Genetics by & for Top BreedersGENETIC TESTING

 

Responsible breeders seek the latest genetic certification; others substitute "clear" dogs for those that might not pass certain health tests. Selectively blind to visible defects, breeders are building a gene bank destined to collapse in bankruptcy!

 

 

 

PAINTING THE GENE BANK

 

Barbara J. Andrews, TheDogPlace.org Publisher

 

In the mid-80's, novice dog breeders rushed to test for VWD (von Willibrand's Disease) while accusing everyone else’s dog of having it.  In 2016 there are virtually no statistics on incidence of canine von Willibrand's Disease - just a lot of hype about testing. 

 

PAINTING THE GENE BANK WITH POSITIVE CHARACTERISTICS IN YOUR BREEDING PROGRAMA little first-hand background.  VWD was said (by a nobody breeder who had "clear" dogs) to be rampant in Akitas.  My veterinarian, Joel Jensen, said he would test my dogs (Akitas) if I wanted to waste the money but having cared for them for four generations, he figured we’d know if I had a bleeder. “What about a VWD carrier?” I asked. “What about it?” said he. “If you breed a carrier to a clear you might get a carrier. Might not. Since you don’t go out for stud service, the odds of you getting any bleeding disorder are about zilch. But I’ll test if you want…..”  Made sense to me so I skipped the test.  As of this 2016 update, no dog of my breeding has ever had or ever produced VWD.

 

Insight on breeder eyesight - with all the to-do about CHD, VWD, etc. why do breeders not see wobbly hindquarters, popping hocks, sagging toplines, pounding fronts, and faulty temperaments unless they are in someone else's kennel?

 

20 years later... Toy Fox Terrier breeders became excited about DNA testing for congenital hypothyroidism with goiter (ref #1). Curious about how the CHG test came to be developed for a rare condition in a rare breed, I contacted breeders and Dr. Fyfe * ref 1 for statistical data. The response was convincing. Of 32 responses, there were two people who "knew of a CHG affected litter" but only one person reported having experienced CHG. Two others admitted that upon genetic testing they discovered they had a carrier.  Why was the test even developed?  ($$$) This we know.  CHG affected dogs can’t spread the gene because they DIE as infants. The puppy will strangle as the goiter grows.  Nature immediately weeds out that unhealthy gene package just as it does other serious congenital defects unless breeders intercede to prolong life.

 

In the 60's breeders were convinced that CHD (canine hip dysplasia), was a simple recessive defect.  Everyone rushed to their veterinarian for OFA (Orthopedic Foundation for Animals) X-rays.  Vets rejoiced at the extra income and breeders groaned at the expense and agonized over the anesthesia risk.  Then a veterinary friend did a little research and I began to expose the profitable practice that added very little to the canine gene bank but lot of $$$ to the OFA bank.  The problem?

 

1.) OFA x-rays failed to reduce the overall percentage of canine hip dysplasia despite judicious genetic pairings.

2.) Readings were inconclusive and often changed when challenged, re-xrayed or re-submitted.

 

I repeatedly and publicly challenged Dr. Corley in various magazine columns as to why OFA only certified two joints out of at least ten major joints which affect soundness?  Other columnists, breeders, and veterinarians picked up on the subject.  Finally, after years of badgering, OFA began to certify elbows. 

 

But there was still a major flaw in the OFA system, one that affected thousands of breeders who strived to make intelligent breeding decisions based on reliable genetic data.  I continued to challenge Dr. Corley on why OFA refused to require positive I.D. such as tattoo, and later, microchip.  As of 2006 when this was first published, OFA still did not require positive identification of the dog being X-rayed.  I exposed the horrible truth about "Glow In The Dark Dogs" * ref 2 with good hips that were repeatedly substituted for questionable or failed dogs.  Finally, after many years of badgering and bad press, OFA, CERF, and now, CHF require some sort of positive identification.

 

Was There Dishonesty In Deposits To The Gene Bank?

We had been allowed to believe that expending all that time, $$$, and effort was going to prevent something.  Astute breeders wrote or called, saying they had been misled and thanking me for pointing out that almost all health testing, from Xray to CERF is diagnostic, not predictive.  It's like being tested for diabetes or heart disease.  An OFA number only means only that the dog x-rayed normal at that time.  It does not mean he won't develop CHD and certainly is no guarantee that he won't produce it.  So an OFA number is only good for current bragging rights because, c'mon, let's be honest, how many dogs have you re-certified?  If top winning, great-moving dogs can fail to pass OFA while dogs with obviously bad rear movement sport OFA numbers, what does it all mean?  Genetic tests are supposed to clear up any confusion and worry, right? 

 

Breeders might want to re-think the risk of anesthesia just to get a piece of paper that may only be good for a few months.

 

Exactly the same is true of eye exams.  The standard of certification is called CERF, Canine Eye Registry Foundation.  It is a risk-free test, often available at dog shows BUT - it too is only diagnostic.  CERF certification does not mean that the dog won't develop a serious problem such as lens luxation which is what happened to my English import Mini-Bull terrier only two weeks after she was CERF certified!  The real tragedy in that is that I learned it was not that unusual for a CERF-certified dog to literally "go blind."  Most such tests are not predictive and stupidly, I was prepared to breed the bitch.

 

The same can be said of color doppler heart exams.  I know from personal experience and heartbreak.  They cannot predict and they can not reveal genetic factors.  Like most health testing, dopplers are a useful diagnostic tool.

 

You can stop reading right here if you don't like where this is going.  Such tests are important, useful tools.  Every breeder should carry a good tool kit but it isn't the saw and hammer that builds a house, it is the carpenter who knows how to use the tools!

 

Breeding good dogs is not rocket science.  Regardless of the health defect, you would never breed from or to an affected dog.  An affected dog would not be winning in the show ring.  Putting a dog on public display to be examined by a judge might, in itself, be a pretty good exclusionary test for cataracts, primary lens luxation, orthopedic problems including hip and elbow dysplasia, spine, and neck abnormalities, and in fact, the level of exertion required for some dogs to get around the show ring clearly expose heart or airway problems!

 

Perhaps there's a better predictive way to be sure you are breeding to and from healthy dogs.  With the advances in DNA testing, you may be able to ascertain whether a non-affected dog is a carrier for a growing list of health defects.  A DNA swab is non-invasive, unlike x-ray and anesthesia.  It will take some time to see how reliable DNA tests are for VWD, CERF, CHG, etc. but they will be your best tool.

 

For example. your DNA-cleared dog can only produce affected pups if bred to an affected dog.  No way will you knowingly do that!  If the DNA cleared dog produces a carrier, that means the other dog is a carrier.  Can two clear dogs produce a carrier?  Can a clear dog develop the problem?  We're told that in primary lens luxation (PLL) that's possible but the new DNA testing looks like the best breeder tool.

 

If If you plan to advertise a dog at stud, in today's market you better have him genetically cleared for every potential defect known to that breed!  Even so, your competitors will still whisper and insinuate things about your stud's genes.  If your dog turns out to be a carrier, you only breed to cleared dogs.  No big deal.  It is not the end of a breeding career.  Your Doberman might carry blue or fawn but if you don't want that in your line, you don't breed to a dog that carries it.

 

Novice breeders are quick to throw stones at proven (tested) breeders who are slow to jump on every bandwagon. Such breeders know their bloodline, including what dark genes lurk there. They also know that “kennel blindness” occurs on both sides of the lenses.

 

I have written many times "You can live with and love an unsound or sickly dog but a dog with bad temperament is a joy to no one."  It became a popular quote for a very good reason - it's true. Isn't breed temperament and character far more important than proving your dog has good hips, eyes, or heart?

 

An intelligent dog can be a challenge or an interesting canine companion to test YOUR intellectSo how are you going to prove your dog's personality is correct for his breed? Show him!  Take your dog out where other breeders can admire (or reject) him and have him "tested" by people who are paid to assess both physical and mental soundness appropriate to the breed.  AKC dog show judges are pretty darned good at what they do.  Exhibiting your dog (without drugs!) is a great temperament test.  A dog with a sound temperament typical and proper for his breed will produce the most important element of owning a dog - good personality typical of the breed and mental acuity and stability.

 

Puppy buyers have been schooled to ask for health certifications but they don't realize that the sire or dam has to be locked away when visitors come, or that it can't breathe or reproduce naturally!  AKC must have read this over a decade ago because today the American Kennel Club offers Canine Good Citizen tests in addition to structured Obedience and Agility, both of which test a dog's I.Q. and stability.

 

There is one reality we must face before we get all wound up about the latest, newest, desperately needed DNA test or health screening.  In spite of all that we do, genetic problems are increasing.  Every year new diseases are diagnosed in companion animals.  It isn't that researchers and vets are getting better at what they do.  It is a sign of the times and equally true in the human population.  Just thought I'd mention it...

 

So even with all the tests, are breeders able to fix canine eye, heart, organic, reproductive, and orthopedic defects?  We haven't made much progress in some breeds with problems we can SEE.  A casual look around any show ring clearly reveals some breeders would rather paint their gene bank with paper certificates than with good structure, health, and temperament.  If you doubt this, see Health Defects in Purebred Dogs (3) study the then and now photos and don't be discouraged, be inspired to do better and work harder in your breed club.

 

Maybe the answer lies in human nature. If we can buy bragging rights for a hundred bucks, that is enough for some breeders.  My repeatedly (and ignored) suggestion is that all breeding dogs should earn a champion, field, obedience, or agility title before they are bred regardless of how clean the genes are!

 

Genetic testing is a useful tool. Think of it as one of many brushes in the artist’s case.  Do we teach breeders to step back and view the landscape before splashing color on the canvas?  Or do we encourage them to paint with just one color, knowing that our canvas will easily win over theirs?

 

I don’t have a lot of letters after my name. I just have a lot of top ranked winners and producers. I’ve been creating juried (judged) works of art and like many others who learned the hard way, I did it before we had such wonderful tests and tools. We learned “genetics” before words like polygenic, homozygous, and DNA were invented! We will gratefully use what science has afforded us but the test has yet to be invented that will replace logic, attention to detail, pedigree research and hard work!

 

If we have truly learned anything about genetics while painting our gene bank, it is how to create a masterpiece that can be reliably reproduced. That is the challenge.

 

(ref 1) DNA testing for congenital hypothyroidism with goiter - the farce behind the hype

(ref 2) X-ray Radiation Risks that create glow on the dark dogs

(2) Health Defects in Purebred Dogs

 

Portions excerpted from ShowSight Magazine columns, circa 2006

062163

click to send this article to friends

 

Genetic Problems

Eradicate luxating patellas, CHG, VwD by reading pedigrees.

DNA Cryptochid Fraud

University Reps collect saleable blood for "missing testicle" study.

Was Darwin Wrong?

Control the way genes combine to set canine characteristics!

Free Subscription to HEADlines from TheDogPress

 The United Kennel Club

Real Dogs For Real People

Canine Reproduction

CANINE REPRODUCTIONS MEANS SUCCESSFUL MATING, WHELPING, AND VIGOROUS PUPPIES

Peer-reviewed articles by Top Reproduction Specialists!

 

back to Canine Genetics Section or explore

 

TheDogPlace.org for authoritative free DogCare information.

If you breed or show dogs, get your news at TheDogPress.com

Judges and handlers, be sure to visit TheJudgesPlace.com

 

*None of the statements contained herein as regards human or animal health have been evaluated by the FDA.  Information is provided for educational purposes only.  We are required to advise you to always check with a licensed veterinarian or medical doctor.  Information or products offered are not intended to diagnose, treat, cure, or prevent any illness, disease, or condition, whether animal or human.  This disclaimer is due to FDA restrictions designed to protect you, the consumer.  It does NOT however, protect you from malpractice, prescription drugs, or vaccines.