[Guest]

How long will it be until someone with authority on the matter admits the possibility (probability?) that the prcd form of PRA may not affect Goldens as it does other breeds?

I have only been in the breed 14 years, but I know a heckuva lot of Goldens, not just regionally, but nationally. I know of exactly ONE that has been found to be clinically affected, i.e. experiencing dwindling eye sight. How many do you all know of?

With more and more dogs being tested, we are discovering that there have been plenty of Carrier x Carrier breedings. This would suggest that these breedings have unknowingly been going on all along and I have yet to hear stories about dogs going blind.

I am not suggesting we throw caution to the wind, but am I the only one who would like to know if this is a wild goose chase?

 

[stevelow]

There are two Goldens listed on K9data and Golden DNA that tested as "affected" by prcd-PRA.. Does anyone know if these two dogs have had diminished vision? Also, does anyone know if there are more "affected" Goldens whose owners have chosen not to publish the results?

 

[Creek Retrievers]

All though I thought from the beginning that PRA was being blown out of proportion on the internet, it still exists. The reason why you do not see many affected dogs from a carrier to carrier breeding is because it will only affect 1/4 of a litter, so there may only be one dog affected in a litter, and PRA can have a late onset in age. PRA can be controlled through selective breeding but it might mean culling the affected dogs from the gene pool. Also breed carriers to clear dogs.

This is an interesting page from optigen.

http://www.optigen.com/opt9_test_prcdprabs.html

 

[Guest]

Remember, there is more than one kind of PRA. I am specifically talking about prcd-PRA. And you didn't answer my question about how many blind Goldens you know of. Even if only 25% of a Carrier x Carrier litter is likely to be affected, we should still be seeing some blind dogs, no?

Steve, to answer your question, there is at least one other dog that tested as Affected. I do not know the dog, nor do I care to. However, whoever knows who the dog is should be following up with the owner to find out if the dog is demonstrating clinical signs, at what age they first surfaced, how the dog is progressing, if there are any other medical reasons the dog could be exhibiting loss of sight, etc. We all deserve to have that information.

I would sure be interested in knowing if and when more research will be done on how this affects our breed and Optigen sure isn't going to be the one to do anything to discourage us from testing!

 

[Steve Amrein]

It seems that even a large amount of vets do not know about the test similar to EIC in labs.

I have never seen or heard of a dog that has had blindness caused by PRA.

Do we know of what % of affecteds will actually develope symptoms ?

What degree of accuracy is the testing ?

While I understand the need for testing some will profit by doing the testing.

What will the "next" test be for?

I also wonder at what point will we be losing something from the breed as the gene pole gets small one bit at a time.

 

[Guest]

Do we know of what % of affecteds will actually develop symptoms ?

This information, which in my opinion is crucial, is not currently available for Goldens.

 

[stevelow]

The two Affected Goldens which are listed are 7 years old and 1 1/2 years old. Even the older one may be too young to show any symptoms.

 

[Guest]

Sorry, I probably wasn't clear. The other dog I was referring to is not listed as being Affected on k9data or goldendna.

The 7-year old (listed on both sites) is exhibiting some loss of sight, but is it from prcd-PRA or is it perhaps due to something else?

 

[D Osborn]

So, basically I overreacted due to Optigen saying this will happen for sure and it is not. Hmm Isn't that Nice.

A little pissy about this, and I think we jumped on this bandwagon a little quickly. What if this prcd thing does not mean blind dogs.

How sweet.

Becky Mills can translate the southern slang.

 

[Becky Mills]

Au contraire, Miz Demi. You covered it perfectly with your Junior League version.

 

[Creek Retrievers]

Remember, there is more than one kind of PRA. I am specifically talking about prcd-PRA. And you didn't answer my question about how many blind Goldens you know of. Even if only 25% of a Carrier x Carrier litter is likely to be affected, we should still be seeing some blind dogs, no?

Steve, to answer your question, there is at least one other dog that tested as Affected. I do not know the dog, nor do I care to. However, whoever knows who the dog is should be following up with the owner to find out if the dog is demonstrating clinical signs, at what age they first surfaced, how the dog is progressing, if there are any other medical reasons the dog could be exhibiting loss of sight, etc. We all deserve to have that information.

I would sure be interested in knowing if and when more research will be done on how this affects our breed and Optigen sure isn't going to be the one to do anything to discourage us from testing!

To play the devil's advocate, I do know of one pup out of a litter of four that was affected with PRA, most likely prcd-PRA and it was early onset, he eventually went blind. This was well before the DNA test and now the affected dog and littermates are dead, so again no evidence. I am not sure what your looking for Mel, I know I am not going to play with fire, breed carrier to carrier to see if any are affected, wait and see how bad their vision or if they go blind. Why do that when you can breed to prevent it? I rather not deal with angry puppy buyers down the road if I don't have to.

 

[Guest]

most likely prcd-PRA and it was early onset

Where do you get the "most likely prcd-PRA" assumption? Without a DNA or clinical diagnosis, it could have been another form of PRA.

Define "early onset."

Melanie

ps Before anyone thinks I am getting rude (gawd forbid I ever do that), I know Becky knows I am just asking questions, not going after her.

 

[Guest]

From the Optigen site:

"Conditions that seem to be prcd-PRA might instead be another disease and might not be inherited."

 

[Gerry Clinchy]

How long will it be until someone with authority on the matter admits the possibility (probability?) that the prcd form of PRA may not affect Goldens as it does other breeds?

You're not the first one to ask that question

To have scientific proof this test works as accurately/reliably for Goldens as it has for other breeds, we will need more affected Goldens to be tested. The original research could not validate for Goldens, because they couldn't find affected Goldens to include in the research.


Because the identical mutation has been found in the many other breeds (18 or 19?), the Optigen website states: "In every year since the mutation’s discovery, new breeds have been identified in which the same prcd mutation is shown to be associated with PRA. This leads one to conclude that prcd-PRA must be quite an old mutation and that it likely arose in the dog population before many of the breeds were segregated into distinct “closed” breeding structures."

I don'tt know what the exact # would be to get this proof, but someone has mentioned ten.


Part of the task is to locate the existing affected dogs. I won't be the one to purposely breed two carriers in order to produce new affecteds. You might have to do such breedings a number of times since only about 1/4 of the resulting offspring might be affected. Roll of the dice, could also dictate none would be affected.


Quicker to get the answer if someone were willing to breed two affected dogs to each other. I won't be volunteering to whelp that litter either.


I have only been in the breed 14 years, but I know a heckuva lot of Goldens, not just regionally, but nationally. I know of exactly ONE that has been found to be clinically affected, i.e. experiencing dwindling eye sight. How many do you all know of?

I have been in the breed for 40 years, & I now know of 2 now living. I know of 3 who are deceased; & 2 others whom I'm not sure are still living or not. I never knew of these deceased dogs when they were alive.


I get the sense that when these occasional cases turned up, a lot of neutering took place & that seemed to solve the problem. With a recessive gene it would appear to do so for quite some time.


Let's not forget, PRA (in any form) has long been considered rare in GRs, so the neutering solution was pretty effective, except for the few who might have escaped the purging.


Because the gene does not frequently occur in GRs, the few carriers who escaped purging could remain un-noticed for a long while.


However, it would only take one popular sire who is a carrier to spread the gene quickly; & subsequent linebreeding could change the whole picture for the breed.


In addition to these, one dog is listed on www.GoldenDNA.com that has been dx'd by test, but is younger than physical symptoms usually occur. However, the Optigen website states: "We have also found a few other golden retrievers to be genetically affected through OptiGen testing, however all of these dogs are still less than 3 years old and therefore below an age where clinical diagnosis is likely to be observed."


I think of "a few" being "three or more", Others may have another opinion.


The owner of the dog listed on the database fully intends to carefully watch the dog's progress. Optigen asks: "We ask anyone with PRA affected dogs to please keep OptiGen updated with any changing information on their dogs’ eye examinations so that we may add to the understanding of this disease in all breeds."


Looking at the pedigree of the dog listed, it seems logical that this dog could be affected.


With more and more dogs being tested, we are discovering that there have been plenty of Carrier x Carrier breedings.

I think there may be 5 or 6, but haven't precisely counted. To my knowledge, none of those breedings has been able to track down 100% of all offspring.

This would suggest that these breedings have unknowingly been going on all along and I have yet to hear stories about dogs going blind.

There are a number of reasons for this:
1) dogs in pet homes whose vision is not strenuously tested; & who do not regularly attend eye clinics; petowners may not consider it unusual for a 10 yr old dog to be blind;
2) some may "wash out" of competitive homes when they don't appear to fulfill their early marking or handling skills & end up being part of 1);
3) some of these dogs may die of other causes before the deficiency of vision is noticed;
4) some people may not talk much about those they do find;
5) it is obvious from some of the carrier X clear breedings that we have been way luckier than anyone should expect to be. (But "luck" can be fickle)


I am not suggesting we throw caution to the wind, but am I the only one who would like to know if this is a wild good chase?

Jerry Bailey (Golden owner & field trial judge) spoke with Optigen in depth. He acknowledged that we still lack a sufficient number of affected dogs (who also test as having a duplicate copy of the mutation) to give us the scientific proof we seek.


Being a medical doctor, he recommended that our approach should be one of "do no harm". As we seek the proof that will give us scientific confidence, we proceed with caution. We avoid breeding carriers to carriers, so that no blind dogs will be produced.


It is important to find whatever affected dogs may now exist, since I doubt any of us wants to consciously produce new ones.


The oldest ones will be the most expedient help. If those older affected dogs have physical examinations showing them to be affected, they are tested by Optigen for free. Even most petowners can afford the $30 once a year for an eye clinic exam.


Nope, I don't believe this is "smoke & mirrors". I believe it's a valid path to pursue & it's a win-win situation. If the test is proved valid for GRs, we prepare ourselves to fend off future genetic testing challenges. If the test proves invalid for GRs, we can move on with confidence as well.


Ignorance of the truth is the only danger. Seeking truth is always a better alternative. Gathering a larger database among Golden Retrievers is the only way we have to get at the truth.


It's important to remember that this first DNA test for GRs is new ground for us. There will be more of these DNA tests in the future. Reading about CNM, EIC, etc. is a glimpse into the future for GRs.


There is a DNA test for a disease known as "Golden Retriever Muscular Dystrophy". The Univ of Missouri, Columbia maintains a colony of Goldens with this genetic disease for research into the human Duchenne's MS, which is similar to GRMD. I'd never heard GRMD until a few weeks ago! Yet, it does exist.


GRs have an incredible opportunity to deal with a disease like prcd-PRA which is relatively rare (v. other breeds). We will learn to deal with DNA testing as a breeding tool from the safety of the "high ground".


Each time a new DNA test is developed, we'll have to answer the same question: how can we be sure the test works? Each time we'll have to deal with some uncertainty as we seek the truth. Each time we'll have to proceed with caution, & remember Jerry Bailey's words: do no harm.

 

[Creek Retrievers]

Where do you get the "most likely prcd-PRA" assumption? Without a DNA or clinical diagnosis, it could have been another form of PRA.

Define "early onset."

Melanie

ps Before anyone thinks I am getting rude (gawd forbid I ever do that), I know Becky knows I am just asking questions, not going after her.

That is not an assumption, it was diagnosed by a veterinary opthamologist. Early onset is considered to fall in the age group of adolescence to early adulthood. Most affected dogs show signs between the age of 4-6 years. Anything else, Mel?

 

[Gerry Clinchy]

Remember, there is more than one kind of PRA. I am specifically talking about prcd-PRA. And you didn't answer my question about how many blind Goldens you know of. Even if only 25% of a Carrier x Carrier litter is likely to be affected, we should still be seeing some blind dogs, no?

Refer to list of reasons in previous post ... and everyone acknowledges that all forms of PRA are "rare" in GRs v. several other breeds.

If there are 5 or 6 carrierXcarrier breedings, there may only be 5 or 6 affected.


Steve, to answer your question, there is at least one other dog that tested as Affected. I do not know the dog, nor do I care to. However, whoever knows who the dog is should be following up with the owner to find out if the dog is demonstrating clinical signs, at what age they first surfaced, how the dog is progressing, if there are any other medical reasons the dog could be exhibiting loss of sight, etc.

And if the owner does not wish to cooperate?

We all deserve to have that information.

Up to the owner's own sense of responsibility to the breed at large.

I would sure be interested in knowing if and when more research will be done on how this affects our breed and Optigen sure isn't going to be the one to do anything to discourage us from testing!

They can't research squat without data.

The prcd test was first developed for Labs, using an affected Lab owned by Seeing Eye. The test became available around 1998. But it was only a marker test. Not until 2005 was the test refined to be able to identify the actual gene mutation.

Between 1998 & 2005 there were some false negatives and false positives (I think both, but not sure). When the new test came out, Optigen offered to re-test those dogs who might have been questionable with the marker test.

When there is a very prevalent problem in a breed, then it becomes easier to gather the data. First, because the owners are very anxious to use the test to "fix" the problem; and second, because there are enough affected dogs to "confirm" the test with.

I'd rather be dealing with a relatively minor problem like prcd in Goldens. I had a good friend who has mini Poodles, and you would not have wanted to be in her shoes in the 1970s with PRA.

Optigen states: prcd-PRA is the most common type of PRA and is found in over 20 breeds of dog.

While more than one form of PRA also exists in Poodles, once they had the prcd test, most of their problem with PRA came under control.

 

[Guest]

I have been in the breed for 40 years, & I now know of 2 now living. I know of 3 who are deceased; & 2 others whom I'm not sure are still living or not. I never knew of these deceased dogs when they were alive.

How can it be confirmed those dogs had prcd-PRA?

The owner of the dog listed on the database fully intends to carefully watch the dog's progress.

So where can we find updated information about the two older Affected dogs that have been tested as such by Optigen?

There is a DNA test for a disease known as "Golden Retriever Muscular Dystrophy". The Univ of Missouri, Columbia maintains a colony of Goldens with this genetic disease for research into the human Duchenne's MS, which is similar to GRMD. I'd never heard GRMD until a few weeks ago! Yet, it does exist.

I'm sorry, but I have to ask...so what? If you have never heard of it, how concerned are you about it?

remember Jerry Bailey's words: do no harm.

That is what I have been doing to date. I've tested 12 dogs so far and am following logical breeding practices.

But...

Haven't any of you seen the bumper sticker that says "Question Authority"? I have no qualms about being the one who questions the seriousness of this new "disease"? I obviously don't breed to make friends. I breed to put some healthy dogs who like to do stuff out there.

Melanie

ps The side effect is that I have made some super friends because of our breeding.

 

[Gerry Clinchy]

I have been in the breed for 40 years, & I now know of 2 now living. I know of 3 who are deceased; & 2 others whom I'm not sure are still living or not. I never knew of these deceased dogs when they were alive.

How can it be confirmed those dogs had prcd-PRA?

The question asked was "how many blind dogs" ... didn't specify prcd-PRA. The two now living have been dx'd by an ACVO & have tested affected with prcd-PRA by Optigen.

The three deceased were dx'd with PRA by an ACVO.

Of the two whom I'm not sure are still living, one's owner did not proceed to DNA testing (although it was available at the time); the other was not dx'd by an ACVO, but owner commented "was blind at 10" & produced an affected get & also did not proceed to DNA testing, to my knowledge.

The owner of the dog listed on the database fully intends to carefully watch the dog's progress.

So where can we find updated information about the two older Affected dogs that have been tested as such by Optigen?

The owners must advise Optigen of the progression of the disease. One owner continues to do so. Do not know about the other owner.

There is a DNA test for a disease known as "Golden Retriever Muscular Dystrophy". The Univ of Missouri, Columbia maintains a colony of Goldens with this genetic disease for research into the human Duchenne's MS, which is similar to GRMD. I'd never heard GRMD until a few weeks ago! Yet, it does exist.

I'm sorry, but I have to ask...so what? If you have never heard of it, how concerned are you about it?

The point was simply that just because we haven't heard of a disease, that doesn't mean it doesn't exist.

We won't have to worry about this one very much ... the dogs die from the disease quite young.
remember Jerry Bailey's words: do no harm.

That is what I have been doing to date. I've tested 12 dogs so far and am following logical breeding practices.

And that's just about all we can do right now ... in addition to educating our puppy buyers should they have intentions to breed.

But...

Haven't any of you seen the bumper sticker that says "Question Authority"? I have no qualms about being the one who questions the seriousness of this new "disease"?

I don't see anything wrong with questioning authority if it helps to get at the truth. If I gave that impression, you can erase that.

At this point we need to gather the data that will lead to the answer we seek ... to be able to have confidence in the test ... or not. Without data we march in place & don't move forward.

Data is also needed to get a truer picture of the prevalence of the disease within the breed. I don't think anyone believes that the carrier rate is really 25%. (I don't). The available data so far is heavily weighted toward the first carriers located, not a random sample.

 

[Guest]

The question asked was "how many blind dogs" ... didn't specify prcd-PRA.

See the subject and decide what I was inquiring about.

The two now living have been dx'd by an ACVO & have tested affected with prcd-PRA by Optigen.

And where is the update as to how they're progressing?

The three deceased were dx'd with PRA by an ACVO.

prcd-PRA? If not, why are you mentioning them?

Of the two whom I'm not sure are still living, one's owner did not proceed to DNA testing (although it was available at the time); the other was not dx'd by an ACVO, but owner commented "was blind at 10" & produced an affected get & also did not proceed to DNA testing, to my knowledge.

I'm a little curious as to why folks are getting upset for me questioning this. I would think y'all would be wanting answers like I do.

Melanie

 

[Klamath Hunting Gold]

Mel Mel,
thanks for asking the questions.... I have been a silent "wait and seer" for some time now. Perhaps a nay-sayer would be a better way of putting it.

I'll be shooting your birds for you in the Derby tomarrow. May the force be with you.

Amber went out in the third in the qual... Not bad for a preggo dog.

Randy