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Preliminary DNA test for Early Adult Onset Deafness now available!


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Early Adult Onset Deafness (EAOD) is an inherited deafness that strikes Border Collies in their prime (3-7 yrs). Dogs begin life with normal hearing, and go deaf in adulthood. Research attempting to isolate the gene(s) that cause this condition has been ongoing, and a preliminary DNA test is now available through projectDOG!

 

Contained within the short sequence of DNA that causes EAOD are five mutations close to one another. Each could conceivably alter gene function and produce deafness. It is probable that only one of these mutations is the true cause of EAOD. The current preliminary test will give Normal, Carrier, or Affected results with a high degree of confidence and validity. A small percentage of dogs will have "Inconclusive" results, and those are the dogs needed to finalize the research for the specific target gene.

 

The preliminary test is expensive to run as they are currently testing five suspect markers. The researchers need a significant population of dogs (approximately 1,000) to find the small group of Inconclusive dogs. Aggregate data from all dogs analyzed will help discern which of the candidate mutations is the actual cause of EAOD in Border Collies, to provide a financial sustainable model of testing the target marker (rather than five). In order to reach this goal, projectDOG expects to offer EAOD testing until September 30th, 2016. If, however, the demand for testing by the working Border Collie community is not strong, they may close testing sooner.

 

Added value to encourage testing! Advances in DNA tech platforms have made it so that the cost of testing one or a few variants is the same as testing many variants. This means that without any additional cost, projectDOG can test and provide results for additional health risks in the working Border Collie breed. The tests included with EAOD are CEA, I-GS, and Mdr1.

 

Most of this information has been mined from the projectDOG website, https://fidelis.projectdog.org/ and questions about the research and testing are best directed not to me, but to the projectDOG team, whose contact information can be found on the website. The site also has an FAQ page.

 

I am sharing this information in the hope that it will personally benefit individuals and their dogs, as well as the Border Collie breed as a whole by reaching that research goal. I've ordered tests for all my dogs and am looking forward to the contribution they'll be making to this research. I hope many of you will join me!

 

 

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Hello everyone,

 

Thank you, Megan, for posting this exciting news! Early Adult Onset Deafness is a real issue for our breed, and it is wonderful that the DNA test is available. This important test is one a several that should be utilized by anyone breeding Border Collies, and anyone considering purchasing a Border Collie puppy should make certain that the parents of the puppy has been tested.

 

Regards to all,

nancy

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Be prepared to wait years for this testing to identify the causal gene for EOD. The causal gene cannot be identified without knowing the EOD phenotype of the dogs tested.

 

Hearing dogs under 8 years could be: clear, affected, or carrier

Hearing dogs over 8 years could be: clear or carrier (EOD phenotypes of offspring are needed to identify carriers)

 

If the testing is mostly performed on 3 year olds these dogs will need to go deaf or reach 8 without hearing loss and have been bred before phenotypes can be assigned.

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Hi Mark,

 

It seems as though you are saying the results from the preliminary test will not be valid. Are you referring only to the "exceptional" outcome results?

 

The projectDOG website says,

 

Most Cases, Most Outcomes

 

-The DNA test tracks 5 linked DNA variants.

-These variants are usually co-inherited.

-When that happens, the test result is definitive.

-Even though the causal mutation is not known.

 

Reliability & Validity -- Same as other DNA tests

 

(Emphasis, and any typos, are mine.)

 

The "Rare Cases, Exceptional Outcomes" are the ones reported on the page as "Results Uncertain, but Inform on Causal Mutation," and this is copied from the website (sorry about the formatting):

 

"Discovery DNA Testing

The candidate mutations are typically co-inherited, such that the DNA results are unequivocal for most dogs. The rarer instances when mutations have been reshuffled hold the key to excluding non-causal variants and pinpointing the single causal mutation."

 

Could you please clarify what you are saying above? Are you simply saying that it it could be years before a FINAL test is available that will provide unequivocal results for ALL dogs? It seems to me from the above information that the current test will reliably identify the status of *most* dogs. Thanks!

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What I don't understand is the Hurry, Hurry! Limited time offer! Get your money in NOW!! part of this. Is this how research institutions usually operate? If this disease is a big problem and if large numbers of samples are important for research and if this is a valuable test, why are they going to stop it all in September? Or even sooner?

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If you are submitting samples to know the results of the suspected EOD variants that are part of this test, those results will be available after the testing is run. Based upon my inside information samples will be run in large batches not necessarily immediately upon receipt.

 

If you are submitting samples to help identify the causal mutation for EOD don't expect the causal mutation to be identified until after the phenotypes of the tested dogs are known (years).

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The reason a DNA Test for EOD is being offered to the border collie community is that it will benefit most breeding decisions now, and many of us in the community really need this information now so as not to keep producing affected dogs (and suffering the heartbreak and perpetuation of this genetic disease). Border collie owners and breeders have pushed for this to happen. The researchers are willing to do this because it can benefit both breeding and research.

Mark, you have commented that the EOD research may take years to be concluded because the dogs being tested are likely to be young. Dogs must be 8 yrs or older before they can be said to be clear of EOD.

The research group is well aware of this and the current approach includes a solution to this problem. This approach to address informative dogs is touched on in brief on the website.

If a young, breeding-age dog is found through the DNA testing to have the informative (reshuffled) pattern of mutations. This young dog likely inherited this pattern of mutations and it is not unreasonable to expect that relatives of this dog, including older relatives, also hold this same pattern. It is my understanding that these mutations tend to be co-inherited. When the mutations are reshuffled, they tend to stay reshuffled in the particular pedigree.

The young dog that was found to have the important (informative) DNA pattern in this example serves as a beacon for finding older dogs that share this pattern.

The researchers have said that DNA from these older relatives will be collected and analyzed at no-cost to the owners.


If the older dogs share the important pattern, a hearing test will also be provided at no cost to determine the phenotype of the older dog carrying this pattern. Perhaps some of these dogs might have BAER tests already from ABCA sponsored clinics at National Finals (I hope)!

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Mark

My understanding is that batch sizes will be processed at about 100 samples per batch. This doesn't seem extraordinarily large….certainly not in light of the enthusiastic response that is being expressed over the past several days.

 

Haystack

The limited time offer has to do with Mark B's concern about batch sizes as well as sustainable economics. If there is strong response, then batches will be filled and processed timely as committed on projectDOG's website. In order to keep costs to a minimum, chips need to be processed in economical batches. If demand tapers off, then batch processing could be delayed…..rather than have owners experience long delays (and unsatisfactory service) or baring the unsustainable cost of processing smaller batches, the project could be canceled due to lack of demand.

 

If demand remains strong, then the project may well continue past September.

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I no longer have any registered border collies; for quite a few years now all my dogs have been rescues with unknown backgrounds. But if I did, I would absolutely be having them tested to contribute to the research. This is a matter of putting your money where your mouth is, IMO. If, as a community, we aren't willing to do something about EAOD rather than just talking (or complaining) about it, then it'll continue to be a problem in the breed.

 

As some background to demonstrate that I'm not just talking from the safe place of only having rescues and therefore not having to lay out any money in support of my opinion, I submitted and paid for OFA certification (pre-PennHIP) of a clearly dysplastic dog. Many people wouldn't have bothered -- didn't bother (and probably still don't) -- to submit obviously affected X-rays , but I believed, and still do, that it's important to include them in the data for a more comprehensive understanding of the scope of incidence in the breed.

 

So I do hope people will take this seriously and participate in the testing and collection of data.

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Thanks to all involved!

 

By the way, if you have an affected dog that has been confirmed by BAER test, you can request to submit a sample at no charge. Check in the FAQs under "What if my dog is already affected by EAOD?" It is very important to have a good number of affected dogs in the database as well as clears and carriers.

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Does this apply to dog's whose pedigree would probably not be related to any dogs in the US?

 

 

Absolutely. EOD has been found in dogs whose bloodlines come from the US, Canada and the UK. I haven't heard one way or the other about dogs from Australia or New Zealand ...

 

I'll be doing my boy Nick soon, too.

 

~ Gloria

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This is vital research *and* testing that will only progress and yield results if enough owners/breeders are willing to make the effort and pay the expense for testing. Generations of dogs and those that depend on them and enjoy their companionship will benefit from the knowledge this study and testing will provide. But it will only happen if there is enough interest to move the project forward. Please share with those you know who can help make a difference!

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Even if you have no intention of breeding your dog, you can order the testing in order to support the research. This is a heartbreaking condition to deal with, be it a pet or working dog.

 

We are being offered a unique opportunity to not only support the final phase of refining the test, but also to get results ASAP on our dogs. For those of us who do breed, it will help preserve bloodlines that will contribute important traits to the gene pool while avoiding producing any more affected dogs.

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I, too, am curious as I know ABCA has a volunteer ream that has worked hard to deal with health issues and promote sound practices. I'd like to hear their input on this.

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