Moonlake Posted November 18, 2011 Share Posted November 18, 2011 I raised this question in the Carrier thread and as advised, am starting a new one on the subject. Renal dysplasia as an inherited condition has recently been found in UK whippets. The good news is that there is a dna test for the condition which is not breed specific - more info on the subject here https://www.dogenes.com/JRDarticle-en.pdf The website of dogenes that offers the test lists 33 breeds known to be affected to which we must now add a 34th of whippets. The bad news in this condition is that the mutant gene is dominant, with incomplete penetrance which means that a dog with only one copy can still become ill and die - after it has been bred from. The penetrance of the disease is thought to be only 5% (obviously, not in individual litters as it was the death of two puppies in a litter that started the enquiries and their parents were found to have three copies of the mutant gene, previously unknown in the breed, between them). We are trying to raise money to fund the testing of 50 random whippets and in the meantime, some of us are testing our own stock. I have sent off four sets of swabs today and am waiting for the results with some trepidation. This is new territory for whippet breeders who have until now been in the comfort zone of no known (to the Kennel Club) inherited diseases so I am hoping to find on this list, people who have experience of dna testing their stock (especially if for rd or jrd) to ask them what is the protocol, particularly for a dominant gene where there is only a 5% chance that a puppy with it will be ill? Do you test all puppies and put down regardless those with even one copy? Do you sell them? What do you tell the buyers - that there is a 5% chance that their puppy may die before it is two years old? The mother of the puppies that died has two copies and seems perfectly healthy and so were the puppies from her first litter - so far. Has anyone any experience of this kind of time bomb? Link to comment Share on other sites More sharing options...
sandgrubber Posted November 21, 2011 Share Posted November 21, 2011 Bump. Interesting question. Hope you get some useful feedback. Link to comment Share on other sites More sharing options...
*Lolapalooza* Posted November 21, 2011 Share Posted November 21, 2011 If you Google 'PNP' you can find info on renal dysplasia in Bernese Mountain Dogs. It is infrequently seen in Scandinavia and any male who produces it is removed from the gene pool. I dont believe there is a DNA test for BMD's but would love to know if the whippet test is appropriate to our breed Link to comment Share on other sites More sharing options...
Lowenhart Posted November 21, 2011 Share Posted November 21, 2011 (edited) I think that the breed clubs could do well to sit down with a geneticist and come up with strategies to maintain the breed and begin reducing the prevalence of the RD allele. Edited once I found the link here - http://www.dogenes.com/ I'm not qualified draw up the rules but I would personally recommend - Test EVERYTHING. Find out the % of dogs with the mutation. Restrict breeding where both parent dogs have the mutation UNLESS the mutation is widespread. If the mutation is in > 50% of the population, stipulate the restriction on breeding of dogs who are homozygous for the mutation (have 2 copies) and recommend that clear puppies are selected from the litter where possible. (We want to keep as many dogs in the breeding pool as possible, so keep the heterozygous in to try for clear offspring) Puppies will need to be DNA tested. Those with the mutation should be sold with full disclosure and a list of possible symptoms for the new owners. Restricted breedings can be done with approval, but aren't recommended (you'd need a good reason for doing so). Just my 2 cents (having studied a little genetics at uni). Edited November 21, 2011 by Lowenhart Link to comment Share on other sites More sharing options...
Moonlake Posted November 21, 2011 Author Share Posted November 21, 2011 Thanks, Guys. As I am sure you know, it will not be easy to persuade breeders to dna test anything, let alone everything, since nobody thinks they have this in their line. I think it is fair to ask that if this is a potentially fatal disease from just one copy of a mutant gene, how come we have never even heard of it, let alone knowing about puppies becoming sick and dying. However, in every breed, there are breeders in denial about health problems in their line and unwilling to accept that the only way to overcome a problem is to share knowledge. This could be why we have never heard of it, coupled with vets not realising that kidney disease could be inherited and thinking it idiopathic and basically bad luck. I suspect that it is not just one basic mutant gene but a more complex inheritance and I had hoped to hear from people who were already testing for this and whether pedigree analysis had shown any patterns. The Dogene dna test is not breed specific so anyone can get their stock tested. If it is a breed not already listed as affected it would probably be worth asking for special rates (we were offered the litter rate for any unrelated dog we wanted to test) as they are keen to widen their database of breeds and their incidence. I may have looked at the wrong Bernese site because it wasn't mentioned on the American club site. I have talked to a gundog breed here that have started to test for it but it has not been easy for them even though they already test for familial nephropathy. It is easy to say, don't breed from anything carrying the mutant gene but only 5% of those with one or two copies develop clinical signs which can be mild, late onset or severe enough to be fatal in youth and that is not a compelling argument for a breeder who has been producing puppies for years without any sign of it. If their dog/bitch tests positive, should they immediately stop breeding from them? UK whippet registrations are in excess of 3000 per annum and that includes plenty of puppy farmers who are certainly not going to start testing their stock. We don't have to have a strategy to preserve the breed, there are plenty of them (although the winning show dogs come from a fairly small gene pool) but a strategy to know more about the disease and its mode of inheritance would clearly be a good thing. We also do not want to start a witch hunt on specific lines just because a couple of breeders have been entirely honest and open about the problem which is certainly not their fault. Is this thought to be a rare disease? Is anyone on this forum in a breed that has another rare or uncommon disease and do the clubs have a strategy for it? I am really just trawling for info in the hope that there are some breeders who do not think that any talk of breed problems is taboo and likely to end in lawsuits - our dogs are our family members and surely anything we can do to protect them or improve them should be done? Link to comment Share on other sites More sharing options...
Lowenhart Posted November 22, 2011 Share Posted November 22, 2011 If the breed club is not interested in handing down guidelines then it's up to you to lead by example - don't breed to anything not DNA tested. The low penetration means most sick dogs are considered to be a "one-off" and it is difficult to see relationships because all dogs with the gene do not get sick - only a few and at different ages. I don't really know what you are wanting? Your lucky that the DNA test is there, most breeds with rare/unusual illnesses don't have DNA and must muddle through with selecting of stock. Link to comment Share on other sites More sharing options...
Moonlake Posted November 22, 2011 Author Share Posted November 22, 2011 If the breed club is not interested in handing down guidelines then it's up to you to lead by example - don't breed to anything not DNA tested. The low penetration means most sick dogs are considered to be a "one-off" and it is difficult to see relationships because all dogs with the gene do not get sick - only a few and at different ages. I don't really know what you are wanting? Your lucky that the DNA test is there, most breeds with rare/unusual illnesses don't have DNA and must muddle through with selecting of stock. My original query was how do you deal with puppies that have one copy of the gene, given that it is potentially fatal but more likely to have no effect at all. Obviously, you can endorse the registration so that they cannot be bred from but will anyone buy a puppy if they know there is a risk of it dying in the first two years, however small the risk? I was looking for input from someone in a breed who has "been there, done that and got the t shirt". There are 11 breed clubs with varying views on health testing; it seems likely that we will get 50 random whipoets tested plus those from breeders like myself who want to know the status of their stock, however small the risk. Gay Link to comment Share on other sites More sharing options...
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