Saturday, June 12, 2010

AKC Defeats Initiatives to Create Healthier Purebred Dogs

This month's Whole Dog Journal contains a story about Dalmatians that will shock dog lovers.  Although I have been around purebred dogs all my life, I was not aware that Dalmatians in the US and UK, and probably around the world, all carry defective genes that predisposes them to form life-threatening urate bladder stones.  Some Dalmatians have repeated surgeries, while many others suffer and are euthanized.  Genetic testing found that no Dalmatians in the US and UK carry the normal gene -- all are homozygous defective for urea processing.

No one has explained how this terrible defect was carried and spread throughout an entire breed.  The most likely explanations are: (1) the defective gene for urea metabolism has other desirable effects on Dalmatians' characteristics (pleiotropy), or (2) the locus of the defective gene is closely linked (located at short distance on the same chromosome) to a desirable gene (close linkage).  In either case repeated selection for a desired trait brought along the defective urea gene that became universal in the breed.

In 1973, Dr. Bob Schaible, a geneticist and Dalmatian breeder, cross-bred a Dalmatian to a champion Pointer with normal urea processing genes.  Through multiple  generations, he was able to develop Dalmatians that look like others of the breed but with normal genes.

In 1981, Dr. Schaible gained approval of the Dalmatian Club of America and the American Kennel Club to register two dogs from the fourth generation of this backcross.  When the general membership of the Dalmatian Club found out about the registration, however, they caused such an uproar, the AKC refused to register any offspring from these dogs.  Thus, the AKC stopped the introduction of normal genes into a known, studied, defective breed.

Far from making progress toward healthier Dalmatians, the breed club banned any discussion of the topic for 22 years!  In 2008 the membership of the Dalmatian Club of America again voted against registering Dalmatians with normal genes, therefore ALL registered Dalmatians in the US carry the defective gene that causes high uric acid levels and life-threatening bladder stones.

One can despair at the genetic and evolutionary ignorance of average dog breeders, whose misplaced priorities value appearance above health.  But whose responsibility is it to educate breeders and dog owners about canine genetic health and how to improve breeds with major genetic defects?  Most breeds have a few serious genetic threats to their health.  Doesn't the AKC's mission include working for the welfare of purebred dogs and their owners?  Surely, canine health is a major component of that mission.

Mary Straus, writing in the Whole Dog Journal, says "It's time for the AKC to take the lead in improving the health of purebred dogs -- and for breed fanciers to put the health of their dogs above an insistence on genetic purity".    I would add that evidence of "genetic purity" in breeds is arbitrary and illusory.  Most dog breeds have been isolated in registries for less than 100 years, some for less than 25 years, a very short time in dog's evolution.  Dogs are wolves; all dogs share most of the same genes and share 99.8% of their genes with wolves.  What nonsense to talk about breed purity when health is at stake.

In 2008, a British documentary, "Pedigree Dogs Exposed" was aired by ITV.   The shocking video highlighted serious genetic problems in several breeds  -- problems so serious to dogs' health the public was outraged.  How could dog breeders be so irresponsible as to perpetuate these defects?  Public anger toward The Kennel Club and the venerable Crufts Dog Show caused major changes in breed standards and judging, as well as a commitment for The Kennel Club to consider registering dogs from outcross and inter-variety matings to improve dogs' health.  The Kennel Club now registers Dalmatians with normal urea genes.  Not so the AKC.

Here's the bottom line for the AKC:  Genetic testing for major health defects in canines is far advanced over even 5 years ago.  Genetic detection of canine disorders is advancing rapidly. It is now possible to test for many serious disorders that are CARRIED by dogs that appear normal and populate show rings.  Carriers of recessive genetic disorders are the greatest threat to good health in purebred dogs.  Dominant genes can be weeded our by not mating obviously affected individuals.  Affected dogs with two recessives can be removed from the mating pool.  Carriers of recessive defects do not usually show any symptoms but will pass the defect on to half their offspring.  When carriers become champions, thereby desirable mates, the frequency of defective genes in the breed multiplies.

In some cases -- Cavalier King Charles spaniels are the gravest example -- affected individuals are entered in shows and judged winners, when their stunted skulls and growing brains will soon cause them horrible pain and early death. Before the winner dies, however, he will be mated to dozens of females and pass on his defects to many in the next generations of Cavaliers.  How does this make any sense for the health of a breed?  Grossly misshapen muzzles, hips that fall out of their sockets, knees and elbows that freeze or wobble, eyes that go blind -- the litany of avoidable genetic defects in purebred dogs is alarming. -- and most are preventable through sound breeding.

The AKC can vastly improve the health of purebred dogs simply by requiring genetic testing and publishing results of testing for every dog that enters an AKC event.  I am sure the AKC knows such a plan would affect some great show people, some great supporters, members of their governing body, and so forth.  Their reluctance to act on behalf of canine health is political and financial.  Is that a good enough excuse?

Perhaps, for the first 5 years, affected dogs and carriers could be shown, but information about their genetic profiles for significant breed defects would be published in the show program.  After 5 years, the AKC should prohibit dogs affected by or who are carriers of serious health disorders from being shown in AKC events.

Dog shows are designed to select the best  breeding stock for the next generations of the breeds.  Surely, the AKC and breeders want the healthiest dogs to produce the next generation of every breed.  As long as genetic testing is ignored and excluded from consideration, the AKC is not fulfilling its mission.

In Britain, public opinion and loss of sponsors moved Crufts and the Kennel Club to a more informed and proactive stance.  The AKC is not ignorant; it simply lacks the guts to lead ignorant breeders and force malicious breeders into a better practices.

Shame on you, AKC!  Shame on you, breed clubs!

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