Saturday, July 16, 2011

The 2011 ABC Boxer Health Seminar: A Breeder's Viewpoint*

The ABC health seminar was presented this year by Dr Jerold S Bell, clinical associate professor and director of the clinical veterinary genetics course for the Tufts Cummings School of Veterinary Medicine.  Dr Bell spoke for two hours, which included a Q & A session, to a large audience of ABC attendees. The title of his seminar was "Practical Genetics for Boxer Breeders and Owners." 

Overall, the main thrust of Dr Bell’s talk seemed to be to urge breeders to participate in CHIC (the AKC/OFA sponsored Canine Health Information Center), which requires that participants publicly reveal test results.  While I think that's an admirable goal, I also think Dr Bell, a breeder of Gordon Setters as well as a geneticist, exhibited more than a little naïveté with his claim that, "The days of stigmatizing breeders who have produced genetic disease are over." 

But aside from that rosy view of his fellow breeders, Dr Bell's boxer-specific recommendations are what I really take issue with.  Other than cancer, about which there's not a lot we can do at present, the two hereditary conditions North American boxer breeders seem most concerned with today are ARVC (Arrhythmic Right Ventricular Cardiomyopathy, aka Boxer Cardiomyopathy) and DM (Degenerative Myelopathy).

There are currently DNA tests available for both conditions. The ARVC gene test, developed by Dr Kate Meurs at WSU (now at NCSU), has proved to be controversial, with evidence from noted researchers indicating that more research needs to be done before this test can be considered comprehensive and accurate…or not.  (Unfortunately, it appears that Dr Meurs is no longer doing ARVC research.) The only “halfway” reliable method of testing for ARVC at this time is regular Holter monitoring (24-hour EKG), and it is far from foolproof. Nonetheless, the American Boxer Club Health & Research Committee has recommended annual Holter tests for all boxers in active breeding programs.

The DM test, developed by Drs Joan Coates and Gary Johnson of the University of Missouri and Dr Kerstin Lindblad-Toh of the Broad Institute at MIT, et al, is not completely definitive, either, because it hasn't been proven that all boxers with two copies of the gene will ultimately develop DM. However, it has been proven that clear dogs and dogs with only 1 copy of the gene are highly unlikely to develop DM, so with the use of caution, which 
Dr Coates advises, breeders now have a method of gradually breeding away from this horrible disease. Dr Coates' research has been published in the Proceedings of the National Academy of Sciences, and she is currently collaborating with human ALS (Lou Gehrig's Disease) researchers. Her research, currently supported by the AKC’s Canine Health Foundation and the American Boxer Charitable Foundation (, indicates that over 80% of boxers carry one or two copies of the gene she discovered (SOD1). The ABC Health Committee has also recommended the DM test for all boxers in active breeding programs.

After presenting several outdated PPT slides on Dr Meurs' ARVC research on 24 British boxers, Dr Bell recommended that breeders shouldn't bother to Holter-test boxers that had tested ARVC Negative with the gene test, because "if they have VPCs (ventricular premature contractions), there's *probably* another cause for the arrhythmia"!  

His recommendation re the DM test was even more puzzling: Dr Bell said that, in general, DM is seen only in "show lines," and that we shouldn't bother to test for it "unless close relatives of our dog have been affected"! This, despite that DM is a late-onset disease, so one often wouldn’t know a close relative had been affected till the relative was 10 or 11 years old (if he or she didn't die of something else in the meantime); and despite evidence from breeders all over North America that DM *is* currently a big problem in the breed, probably due to the Popular Sire Syndrome, which we see in action every year in the ABC Catalog.

As a boxer breeder with a keen interest in reducing the incidence of hereditary disease in a breed I've been actively involved with since 1973, I was very disappointed in this year’s ABC health seminar.

*Disclaimer: The comments above represent my own opinion, and not that of any other person or organization.

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