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Genetic Testing While Preserving the Best Breed Qualities – Let’s Start the Conversation

One of the most controversial topics, and the most difficult to teach about breeding, is the use of genetic testing and the application of those test results when choosing a mating pair to “improve and preserve the breed”. This is an area where it can often appear, especially to the less experienced breeder, that some prominent and successful breeders are talking out of both sides of our mouths. From one side we say genetic testing is a must if you intend to breed, and then from the other side we say “oh, but don’t throw the baby out with the bathwater” just because the dog is a carrier or affected doesn’t mean they shouldn’t be bred. Improving and preserving the Gordon Setter breed, is nowhere near as simple as choosing to mate only those dogs who pass every genetic clearance. Making the right breeding decision, finding the right sire for a dam… well it’s just not a black or white, right or wrong decision process. So, we’re going to say here, that the first and the most important thing a potential breeder needs to learn, before making breeding decisions, before assuming that the right choice is to breed only those dogs who clear every genetic test, the first thing that potential breeder needs to learn and completely understand is what constitutes a mediocre dog, a good dog and a great dog. With this understanding, one can then come prepared to recognize why, and when it is imperative to include great dogs in the gene pool – and yes, even those good and great dogs who did not clear every genetic hurdle may be needed in that gene pool. Remember, these dogs have many other qualities that are vital to preserving and improving the breed.

Photo by Bob Segal
Photo by Bob Segal

I read an article by Brian Lynn published by Paw Print Genetics that spoke about this topic. I’m sharing Brian’s article here as it fits with what I wanted us to be thinking, learning and talking about…how to use genetic testing appropriately, especially at a time when we must always consider the shrinking size of our breed population and thus our gene pool. We do need to encourage and promote genetic testing. We do NOT need to eliminate every dog who is affected or a carrier, but we do need to aptly apply the judicious choice of the appropriate breed qualities in the dogs we chose to breed. Breeders also need to be able to share every genetic test result on every dog, and they should be able to do so without fear of censor by their peers. The behaviors that cause our breed harm…breeders who cover or omit negative test results…and breeder/exhibitors who gossip about or denounce their peers who have shared information honestly and freely. Compete in the ring with each other folks, we don’t need to compete with each other over breeding choices, stud services and the like, there simply aren’t enough of us left to be that cut throat toward each other.

“When we breed to better a line of purebred dogs, many intangible or subjective variables come into play – conformation, athleticism, intelligence, trainability and more. Mentoring and experience, even the gut instinct borne from these teachings, can make assessing those variables easier. As we learn more and develop an eye for evaluating and reading dogs, the standards for what constitutes a ‘better’ dog, one worthy of breeding, usually rise. The comparative knowledge experience brings allows us to differentiate a ‘great dog’ from a ‘good’ one; what might have been an acceptable to us a decade ago, might not make the cut today. And therein creates the economic correlation of supply and demand among top breeders.

As we eliminate potential breeding partners in favor of ‘better’ dogs, those that will truly improve a line and therefore breed, fewer and fewer potential partners exist. That makes the remaining pool of dogs more desirable and valuable.

When the qualities that elevated a dog to the top of the gene pool are combined with the objective results of canine genetic screening, a breeder is truly ‘bettering the breed’ by passing along the best physical and mental qualities the dog possesses while reducing or eliminating detrimental genes.

However, some people believe genetic testing poses the risk of reducing the gene pool of quality dogs too much. Certainly, if you were to remove every dog that was determined to be an affected or a carrier of an inherited disease, that upper echelon of dogs within a breed could theoretically bottleneck (especially if it’s a small gene pool to begin with); and/or leave dogs that don’t complement and strengthen each other consistently enough to better the breed across necessary qualities, regardless of genetic diversity. True, the knowledge of genetic mutations in two dogs could prevent a top-notch breeding from taking place, but in the big picture of bettering a line and breed, that’s a small concession.

But that’s not how genetic screening works. Genetic screening of canines for inherited diseases provides the knowledge to breed responsibly and with scientific evidence. Breeding to a carrier, or especially affected, dog is a personal decision each of us must weigh, but it can be done safely. Using genetic science, we can determine the mode of inheritance, as well as the variability and expressivity of a gene. With the knowledge of today’s science, we can breed smarter and safer than ever before.

Genetic screening makes a dog a known quantity. Combined with its physical, mental and psychological qualities, genetic screening allows for healthier decision-making choices that truly ‘better the breed.’ The fact that a dog is a known quantity in a gene pool makes it more valuable; a dog’s accomplishments set it apart from the general population, and genetic screening, regardless of results, put it in an even more elite pool of dogs.” read more here

So, this is where the conversation turns to you. I’ve said my small piece and offered food for thought through Brian’s article. Time for you all to join in here and share your thoughts, opinions and questions.

Photographs by Bob Segal

Sally Gift, Mesa AZ

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The CHIC DNA Repository for Gordon Setters

Thank you Jerold S Bell, DVM, Tufts Cummings School of Veterinary Medicine, N. Grafton, MA for your permission to reprint this article.

This article first appeared in the November 2006 TarTan Gordon Setter Club newsletter.
The CHIC DNA repository is a joint project of the AKC Canine Health Foundation (CHF), the Orthopedic Foundation for Animals (OFA), and the Canine Health Information Center (CHIC). It is open to all breeds of dogs. The stated objectives of the program are to: Facilitate more rapid research progress by expediting the sample collection process; Provide researchers with optimized family groups needed for research; Allow breeders to take advantage of future DNA based disease tests as they become available; and to Foster a team environment between breeders/owners and the research community improving the likelihood of genetic discovery.
A DNA repository is an endowment for the breed’s future. It is a centralized, multigenerational DNA storage bank. It will allow future, qualified researchers to be able to investigate genetic diseases in the breed. Presently, many funded genetic studies in other breeds have not been completed because of the lack of necessary DNA. By storing DNA from full families and large breeding populations, funded research would not have to wait, as stored DNA samples would be readily available to approved researchers. In order for researchers to have access to the DNA at the CHIC DNA Repository, they must go through an application and scientific review process with the AKC-CHF and CHIC.
If we had the ability to store DNA in during the past twenty-five years from Gordon Setter cerebellar abiotrophy (CCA) families, Dr. Olby at NC State would be studying the disease directly in the Gordon Setter now. Instead, we are relying on progress from the gene search in other breeds to allow comparison with the limited Gordon Setter DNA samples presently collected.
A centralized DNA repository allows for a single DNA collection from each dog to benefit all qualified researchers in genetic diseases affecting Gordon Setters. Currently, individual researchers rely on DNA collection for their own research and storage at their respective institutions. Those samples are not available to other researchers or research projects. Also, those samples may not be saved once the research is completed.
The CHIC DNA registry combines a DNA sample with the dog’s pedigree and medical history. Owners fill out an application and a health questionnaire detailing pertinent health information on the dog. In this way, dogs with specific diagnoses can be identified for future health research. If a dog’s health status changes, owners should inform CHIC to update their information. CHIC will also contact owners approximately every two years for health updates.
The stored DNA is coded so the identity of dogs is not provided to researchers. If further family history or follow-up is needed, contact with owners will be initiated by CHIC.
Due to the initiative taken by the TarTan Gordon Setter Club, Inc an agreement has been reached with CHIC where the fee for blood sample submission for any Gordon Setter is currently reduced from $20 to $10. Cheek swab submissions are $5.
A blood sample is preferable to cheek swab collection, as it contains the largest quantity of DNA. This allows for multiple research projects to use the sample without running out of DNA. Blood samples are sent to the Animal Molecular Genetics Laboratory at the University of Missouri for DNA extraction and storage. If a cheek swab is collected, it is sent to the Veterinary Genetics Lab at the University of California at Davis for storage.
The CHIC DNA repository is a storage bank strictly for research purposes. CHIC DNA samples cannot be used for any other purpose.
AKC DNA profile samples are used solely for identification, litter verification, and frequent sire programs. AKC DNA samples cannot be used for any other purpose.
Samples for the CHIC DNA repository must come from the owner of the dog. If in the past, you donated a DNA sample for other research, you will need to send an additional sample for storage in the CHIC DNA repository.
When a genetic test is developed in the breed, owners can request, at their own expense, that a DNA sample stored in the CHIC DNA repository be forwarded to the established laboratory for testing. If the research to develop a genetic test was done on DNA repository samples, it will be that research laboratory’s decision whether they determine dog ownership from CHIC and notify owners of test results.
More information on the CHIC DNA repository can be found on the CHIC website:
http://www.caninehealthinfo.org/dnabank.html
Requests for reprinting should be made to the author: jerold.bell@tufts.edu

Photo by Susan Roy Nelson

(This article contains photos that are not intended nor do they relate to the content of the article.)