tag:blogger.com,1999:blog-6955843581849132610.post1984765681632227195..comments2023-09-30T04:07:41.831-07:00Comments on The Boxer Underground Blog: The DM DNA Test + a Personal Question for BreedersVirginia Zurfliehhttp://www.blogger.com/profile/02111069072476240750noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-6955843581849132610.post-22410492215542279452011-08-30T09:50:21.164-07:002011-08-30T09:50:21.164-07:00>> Breed-wide screening for DM won't dec...>> Breed-wide screening for DM won't decimate the breed<br /><br />I guess we're getting into semantics, now. I've always been taught that a "screening test" is used to "screen out" affected dogs. (Like a screen window keeps bugs out.) In that sense of the term then yes, breed-wide screening for DM (which means removing all At Risk dogs, and most Carriers) will, in fact, decimate the breed. <br /><br />Breed-wide *testing* for DM won't, of course; it's the use of the test as a screening tool to remove most or all dogs that possess the DM gene that becomes problematic.Jenhttps://www.blogger.com/profile/01698514186799299219noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-43040555200161327292011-08-30T08:12:28.966-07:002011-08-30T08:12:28.966-07:00Jen,
Breed-wide screening for DM won't decimat...Jen,<br />Breed-wide screening for DM won't decimate the breed; making the DM test the sole criterion for breeding decisions WILL decimate the breed. Most serious breeders understand that. Dr Coates has repeated that over and over again. But many breeders have no way of knowing which, if any, close relatives of their breeding stock were or, more to the point, *will be affected* by DM. <br /><br />I certainly didn't know that back in 1989 when I bred what would turn out to be my first DM affected boxer. And I didn't know back in 1994 when I bred that bitch at the age of five to a five y/o stud dog that both of them would end up being affected; and that therefore my whole litter of 4 was going to be affected.<br /><br />I don't know what Dr Bell meant, I only know what he said; and IMO, what he said about both DM and ARVC has the potential to put our breed right back where it was in 1994 vis a vis those two often fatal diseases, if present-day breeders heed his advice.Virginia Zurfliehhttps://www.blogger.com/profile/02111069072476240750noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-20796123116213339962011-08-30T05:37:07.402-07:002011-08-30T05:37:07.402-07:00I've checked my notes, and they differ slightl...I've checked my notes, and they differ slightly from yours. :) I wrote down:<br /><br />"'You will decimate your gene pool and destroy your breed' if you use this as a breed-wide screening test. Use as a screening test only for those dogs with close relatives affected."<br /><br />Which explains why I wasn't as appalled as you were by that portion of the talk. ;) He probably said "use it only for dogs with close relatives affected" and we heard "it" as two different things. Regardless, I think we both agree that using the test as a sole breed-wide screening tool is just as foolish as not testing at all, regardless of family history.Jenhttps://www.blogger.com/profile/01698514186799299219noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-36325050036580657272011-08-29T11:41:18.678-07:002011-08-29T11:41:18.678-07:00I took notes, too, Jen, and was so shocked by Dr B...I took notes, too, Jen, and was so shocked by Dr Bell's statement that I wrote to the ABC Health Committee (HRC), of which I was still a member at that time, and pointed out that his professional "advice" was in direct opposition to the testing recommendations on which the committee was planning to base a new ABC health brochure.<br /><br />A friend of mine, also an HRC member, had lost five bitches in quick succession to DM over the past 5 years or so and was speechless with disbelief when she heard Dr Bell say that. <br /><br />My first blog here was a review of Dr Bell's seminar, taken from my (copious) notes. Here is the part I quoted, almost verbatim: <br /><br />"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."Virginia Zurfliehhttps://www.blogger.com/profile/02111069072476240750noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-36232051237687829802011-08-29T10:45:58.163-07:002011-08-29T10:45:58.163-07:00I don't recall Dr. Bell saying that, Virginia,...I don't recall Dr. Bell saying that, Virginia, but I'll check my notes. :) If he did, then yes, I disagree with that statement (and as you know, I disagree with the ARVC-1 statement, too!).<br /><br />I've only been fortunate enough to have one Boxer live past 10 years of age (by four months), and she died before the test was developed, so I can't be much help there. Clearly, my personal experience leads me to focus more on getting them to live to 10 than on what might happen after they turn 10.<br /><br />I know of a dog who was almost assuredly At Risk who died at 10.5 and never showed any signs, but he wasn't tested. My own At Risk dogs are 6 and 2; I'll let you know several years from now how they're doing! (Based on family history, I expect one will never show signs of it and -- knock wood and barring accident -- should live well past 10, and the other has a small chance of doing so and should -- knock wood and barring accident, again -- make to at least 10 or 11.)Jenhttps://www.blogger.com/profile/01698514186799299219noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-45093101481837716502011-08-29T07:22:53.335-07:002011-08-29T07:22:53.335-07:00Actually, what Dr Bell *said* was don't bother...Actually, what Dr Bell *said* was don't bother to *test* unless your dog has close relatives that were affected. That was the statement I took issue with, for two reasons: 1) there's a 5-7 year turnover rate in breeders/exhibitors, and many breeders are not forthcoming about DM, ARVC and many other health issues. Thus, in many cases, a relative newbie doesn't know that his dog has close relatives that were affected. 2) I can name 4 VERY popular sires in just the last 20 years that were affected. And their descendants' name is Legion.<br /><br />So far, I've heard from only 3 breeders with 10+ year-old At-Risk dogs with no sign of the disease. Two of them died ( at 10 and 12) of something else; only one - a 10 y/o -is still alive and symptom-free.<br /><br />IMO, Dr Bell also made some very questionable statements about the ARVC-1 test, but that'll be the subject of another blog. :-)Virginia Zurfliehhttps://www.blogger.com/profile/02111069072476240750noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-80504494198500153422011-08-29T05:40:30.008-07:002011-08-29T05:40:30.008-07:00>> Unfortunately, I know what the penetrance...>> Unfortunately, I know what the penetrance rate <br />>> is for my own dogs so far<br /><br />And I think this is the key for making breeding decisions with dogs that carry the DM gene, in one or two copies. For an At Risk dog with a history of DM in the pedigree, reducing the incidence of that gene is going to be a higher priority than it might for someone with an At Risk dog with no history of DM in the pedigree (even among long-lived dogs). <br /><br />Personally, I've come to treat At Risk dogs just as I treated them before there was a test -- there's a chance they'll develop DM, and family history will give a clue as to how high that chance is; looking at the family history of potential mates will tell me whether to breed those two dogs together. (A high incidence of DM on both sides of the pedigree? Nope.) The test gives me some added information -- I know I can avoid doubling up on that gene if I need to. <br /><br />Think about this, though -- since there is clearly another factor at play with DM, and if it is a genetic one, those Clear (or even Carrier) dogs from lines with a high incidence of DM may be passing on that "factor X" to their get, and down the line an At Risk puppy could be born that will then have that "trigger" to lead to DM. We can't look at the gene test results and stop, as far as DM is concerned -- family history is important, even in the Clear and Carrier dogs. I believe -- or at least, I like to think ;) -- that's what Dr. Bell meant when he said not to use the DM test as a screening tool. He didn't mean don't use it at all -- he meant don't use it as a sole means to remove or include dogs in breeding programs.Jenhttps://www.blogger.com/profile/01698514186799299219noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-59976994991233653052011-08-26T13:42:12.249-07:002011-08-26T13:42:12.249-07:00Thank you for reading the blog, Cindy. :-) I agree...Thank you for reading the blog, Cindy. :-) I agree completely that DM cannot be the be-all and end-all of our breeding programs, but that makes for some very tough decisions.<br />VZVirginia Zurfliehhttps://www.blogger.com/profile/02111069072476240750noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-59848550130373325682011-08-25T13:21:59.026-07:002011-08-25T13:21:59.026-07:00I have one over 10 year old dog that is A/A and ha...I have one over 10 year old dog that is A/A and has not produced symptoms yet, she still runs agility and all things are fine, I am convinced in examing her pedigree and knowing how the dogs died in pedigree whe will in fact die of cancer, time will see if I'm rightJillhttps://www.blogger.com/profile/14068356995514671050noreply@blogger.comtag:blogger.com,1999:blog-6955843581849132610.post-67031136810743071812011-08-25T13:01:37.147-07:002011-08-25T13:01:37.147-07:00Thank you for this blog Virginia! I hope this will...Thank you for this blog Virginia! I hope this will help breeders realize that it will take many, many years to get to the point where there are less "At Risk" Boxers and that one should not eliminate using "At Risk" dogs in a breeding program. It would be detrimental to the breed.CynTech Boxershttps://www.blogger.com/profile/04023674676077569739noreply@blogger.com