The Genetic Tide: Will it Leave Us High and Dry?

WE HEAR MORE AND MORE these days about genetic defects, with good reason. A year ago Time™ Magazine published a pre-Christmas exposé cover story on hereditary problems in purebred dogs. Now the Council of Europe urges EEC member states to adopt its "Multilateral Convention for the Protection of Pet Animals" banning the breeding of animals whose breed points handicap them, regulating breeders in an effort to halt the increase in inherited health problems.
      Many breeds we used to think of as hardy natural types -- even tough Arctic animals like Samoyeds, Siberian Huskies and Alaskan Malamutes -- are now routinely screened for four or five different genetically-related problems. These include deep-seated, serious disorders: central nervous system problems such as epilepsy, immune system malfunctions such as autoimmune thyroiditis. In addition to hip dysplasia, we now worry about osteochondritis, elbow and patella dysplasia, half a dozen distinct eye problems, and more.

At first it was thought that x-rays, screening and selection would ensure genetic health for our dogs. But thirty years of hip x-rays have not wiped out HD, although progress has been made in some breeds.
      Screening and selection for one defect is just fine. But what do you do when suddenly five or six distinct problems must be screened for? Veterinary costs soar. You must select against so many traits that your breeding programme is turned upside-down. Especially if you fancy a serious working breed, as I do: you cannot manage a four- to six-way screening schedule and still select for working ability, breed type and conformation. In a small kennel on limited funds, breeding only two litters a year, it just isn't practical.
      The books on dog-breeding hold no answers. They tell us how to use inbreeding, line-breeding and outcrossing, they teach us the basics of Mendelian genetics; these help to manage one or two traits at a time. But genes don't assort one trait at a time! Genes are linked in groups on chromosomes. While we were all using inbreeding and line-breeding to "fix" desirable traits of breed type and conformation, something else happened, and now we get a steady increase in unwanted traits that we call genetic defects.

The science of "population genetics" is old stuff to wildlife biologists, but few dog breeders in this country know much about it. Yet it could have told us about the problems that we would have by practising artificial selection, breeding from small founder groups with no new gene inflow for decades, using sustained incest breeding without the brutal tempering influence of natural selection.
      Today, when most registered breeds are fifty to a hundred years old, bred within a closed Studbook the entire time, population geneticists tell us that we cannot continue these practices any longer if we want healthy canine companions. They say new genetic inflow is needed to counter random drift in small breed populations and to restore heterozygosity -- genetic diversity -- where it has been lost through inbreeding. They tell us that we are overusing popular sires and add that the German Shepherd Dog, despite millions of actual individuals worldwide, has an effective genetic population of from 400 to 600 animals only! Time-honoured breeding practices are now labelled "genetic genocide".
      Breeds such as Salukis, Siberian Huskies, and Basenjis could easily restore hardiness and diversity by importing primitive stock from their countries of origin, but C.K.C.'s closed Studbook cannot accept such imports.

Perhaps the closed Studbook has outlived its usefulness. In the early days of purebred dogdom, it was a useful device to promote fixation of breed type. Now it has become a dead hand, dragging down the health of our beloved dogs.
      The C.K.C., unlike most other Canadian livestock associations, makes no provision for grading-up, crossing, or new breed development. Its Studbook remains rigidly closed. Each C.K.C. breed is genetically isolated. No protocol exists for the acceptance of new foundation stock in C.K.C. breeds. The Club's procedures seem stuck in a nineteenth-century mould.
      The upsurge in genetic problems -- and the media and government attention they attract -- make it obvious that radical change is needed. The question is, can it come in time? Or is our Club too inflexible to meet the challenge of placing real breed improvement above the demands of tradition and show-ring fashion? Is type more important than health? If we cannot breed healthy, hardy, happy dogs, there are those in our society who will question our right to breed at all.

-- This article was written just before the Seppala Siberian Sleddog became an evolving breed. It was published in "Dogs in Canada" magazine's February 1996 issue. Submitted by DIC to the Dog Writers Association of America annual competition, it won a Maxwell Medallion in the "Essays and Opinions" category for that year.