In recent years, genetic DNA testing has grown in popularity among breeders to determine an animal’s predisposition towards disease and other genetic conditions. This can be of particular value for breeders who wish to determine whether or not a dog is likely to present with a certain disease or even whether it is a carrier of the gene that he could then pass along to future generations. Being able to screen for certain genetic disease can be incredibly useful in keeping highly breed-specific conditions from being perpetuated through bloodlines, by allowing breeding dogs and bitches to be screened before a mating is ever done.
A paper by the Scientific Committee of the Nordic Kennel Union (NKU/VK), however, advises that genetic testing should be used with caution. For one, the tests aren’t fool proof. For example, a test may be done that’s inaccurate or isn’t applicable for a specific breed.
“NKU/VK would like to emphasize,” the article states, “that the importance of a genetic test should be evaluated in relation to other aspects, such as other diseases, included in the breeding goal for a specific breed. Otherwise, there is a risk of too much focus on conditions that are easy to “measure” and record. It is therefore of great significance that the overall breeding strategy of each breed clearly states what priorities should be made in breeding, with respect to all traits included in the breeding goal. The dogs’ overall health status and long-term sustainability with respect to genetic variation are important components in this prioritization.”
The paper also points out that “there may be genetic differences between populations of the same breed in different countries.” It also states that the “mutation that causes a particular disease in one breed does not necessarily have the same effect in another breed.”
Besides the fact that the accuracy and validity of many tests are questionable, there is also concern in how the test data is evaluated. “NKU/VK sees a need for further efforts from the international dog community to support dog breeders and owners with respect to validation and guidance on the use of genetic tests.”
There are even tests designed to detect multiple diseases/genetic mutations. The NKU cautions that “the results of these multi-tests are often difficult to interpret and of a limited value, or even misleading, for breeding purposes.”
The Scientific Committee of the Nordic Kennel Union (NKU/VK) concludes the paper with the following:
“Genetic testing is an excellent tool in breeding for improved dog health, provided that the tests are reliable, relevant and used wisely. Breeders and dog owners should carefully evaluate the benefits and consequences of a genetic test before it is applied. A one-sided or exaggerated focus on DNA test results may result in an increased risk that other important conditions or characteristics are overlooked. The Scientific Committee of NKU would like to emphasize that the breeding program should be based on the prevalence and severity of various health issues, rather than on the availability of genetic tests. If a disease does not constitute a clinical problem in the breed and/or the DNA test offered is not validated or accurate, it is better to refrain from testing the dog. Otherwise, there is an obvious risk of excluding potential breeding animals, and thus decreasing genetic variation, based on uncertain or false grounds. It is important to keep in mind that dog breeding is about much more than specific diseases and that genetic tests, even though today they are many, do not give the entire picture.”
The complete paper by the NKU can be found here.