Genetics Question - Greyhounds At Risk?

[Guest KennelMom]

So...I've been doing some research on PRA and late onset generalized PRA appears to be a genetically linked, autosomally recessive trait in most breeds studied to date (except in Siberian Huskies where it's X-Linked).

 

That begs the question....how "at risk" are our greyhounds in inheriting this condition. *IF* PRA is autosomally recessive trait in greyhounds and Hanna (Fast Movin' Mary) is a direct offspring of Molotov, that would mean that Molotov and Hanna's mom (Dolla Triumph) were both carriers. Molotov has 7639 offpring listed in greyhound-data. Using a traditional Punnett Square (fun!), that would mean that if he was mated to a genetically "normal" bitch, 50% of his offspring are likely to be carriers. If mated to another carrier, about 25% of offspring may end up with PRA.

 

Since this condition has a late onset, it may not even be on the radar screen of racing breeders when deciding who to breed to who. Scary.

 

I know genetics is rarely that simple, but I've touted the greyhound "party line" of how healthy the breed is and how free it is of genetic disorders. Apparently that may not be as true as I thought.

 

Any thoughts?

Edited January 22, 2008 by KennelMom

[turbotaina]

You're right Heather - by the time of onset, most of those pups will be far away from the track and on somebody's couch. The CRRG recommends not breeding known carriers, but unless someone tells the breeders that it's in their lines, they could just go on breeding it ad infinitum. I guess as pet owners, we have a duty to inform the breeders, but I don't know what effect it would have. They would have to weigh out post-race-future versus having great racers in the current kennel.

 

 

 

And, for what it's worth, PRA is one of the few known genetic defects in greyhounds (it's definitely no secret) - so aside from that, hypothyroidism, increased cancer risk and a few other things, they still are way healthier than most other purebred dogs.

[BootsyCollins]

what is PRA?

[turbotaina]

Progressive Retinal Atrophy. The retina atrophies and the dog goes blind. There is no treatment.

[Guest greyaspet]

I had a foster that came into our program at just over 18 months of age and was totally blind by the age of 2 from PRA so it doesn't always show up later in life.

Sheila

[ahicks51]

So...I've been doing some research on PRA and late onset generalized PRA appears to be a genetically linked, autosomally recessive trait in

I know genetics is rarely that simple, but I've touted the greyhound "party line" of how healthy the breed is and how free it is of genetic disorders. Apparently that may not be as true as I thought.

 

Any thoughts?

 

No breed is free of genetic diseases, and if there are any groups "selling" greyhounds as being so, then they are very wrong. PRA is a known issue in Italian greyhounds.

 

Given the number of F1 and F2 (and now F3) dogs from Molotov, if this is a recessive heritable trait, it is something that should be tracked to determine in which familial lines it has been found. Feedback could be provided to breeders.

[inugrey]

In your research Kennelmom have you found a vet who is studying this? Like our Dr. Cuoto and OSU is studying cancer?

We have F2 (thanks Ahicks51 for the terminology) Molotov kids and our vet saw the beginning of PRA in Inu on our regular check up in September. He's at the point where he can still see cats a whole lot better than me! So I have honestly not begun my research.

I'd like to be able to get him and other greys into some sort of study, esp. genetics...

[Greytlady94]

Molotov was my Lucy's sire so I will mention this to our vet.

[Guest KennelMom]

You're right Heather - by the time of onset, most of those pups will be far away from the track and on somebody's couch. The CRRG recommends not breeding known carriers, but unless someone tells the breeders that it's in their lines, they could just go on breeding it ad infinitum. I guess as pet owners, we have a duty to inform the breeders, but I don't know what effect it would have. They would have to weigh out post-race-future versus having great racers in the current kennel.

 

And, for what it's worth, PRA is one of the few known genetic defects in greyhounds (it's definitely no secret) - so aside from that, hypothyroidism, increased cancer risk and a few other things, they still are way healthier than most other purebred dogs.

 

Right...I guess I should have said "relatively" free of genetic issues. But, will the "popular sire" effect make PRA more common in our retired racers? I've read a LOT of adoption sites about greyhounds, I don't recall PRA mentioned as a concern. Though DH told me it's one of the first things he remembers hearing about greyhounds and their health. Maybe I've read about it but read that it was rare so I just discounted it

 

If someone asked me what health issues to be concerned about, hypothyroid comes to mind, TBDs, osteo...not necessarily inherited conditions...but PRA would not have occurred to me. I don't even have any idea how common it is in greyhounds.

 

Given the number of F1 and F2 (and now F3) dogs from Molotov, if this is a recessive heritable trait, it is something that should be tracked to determine in which familial lines it has been found. Feedback could be provided to breeders.

 

I guess that's the heart of my thread. I've not heard of greyhound breeders doing genetic testing on breeding stock like many show breeders do for known issues in their breeds. I'm not even clear from my reading if there IS a test available for greyhounds and PRA.

 

 

In your research Kennelmom have you found a vet who is studying this? Like our Dr. Cuoto and OSU is studying cancer?

We have F2 (thanks Ahicks51 for the terminology) Molotov kids and our vet saw the beginning of PRA in Inu on our regular check up in September. He's at the point where he can still see cats a whole lot better than me! So I have honestly not begun my research.

I'd like to be able to get him and other greys into some sort of study, esp. genetics...

 

I haven't found a vet studying this. The only thing I've found is a site that says "in breeds studied" PRA is recessivly inherited. I've only been looking for about 24 hours, so there could be people out there researching it in greyhounds. I'd be interested if anyone finds anything out there.

 

There are others on this board that are much more educated and up-to-date on greyhound health than I am...I'm hoping they may be able to provide some insight.

Edited January 22, 2008 by KennelMom

[sweetdogs]

I don't remember ever hearing that PRA was prevalent in greyhounds. But obviously, it seems it's not that uncommom. I'd say osteo, pannus, IBD, possibly thyroid, even heart troubles before I'd say PRA.

 

Not to be argumentative, but why would (most) racing greyhound breeders care about things that would afflict the dogs post-retirement? Especially if the genes in question also carry favorable racing traits. I would imagine they wouldn't even know about it until years down the road if at all & in the case of a popular sire, long after the genes had been passed down.

 

I'm very sorry to hear about Hanna's diagnosis. She's fortunate she's got an excellent home.

[jenn8]

After Onyx was diagnosed with PRA, I came up with the same questions. There is actually a program that collects genetic information about certain breeds affected by the disease. My Vet/Opthamologist even told me that it was common in greyhounds and referred me to their web site. Unfortunately, their study does not include greyhounds at this time. Of course, that makes sense as the interest would have to come from breeders.

 

I also contacted Dr. Bradley Fenwick who collects DNA samples from every racing greyhound for identification purposes only. I asked him if there were any other types of studies that the DNA was used for to determine genetic diseases in this breed. Here is his response:

 

Based on recent advances in genetic research, including the sequencing of the genomes of two dog breeds, new information concerning inherited diseases of dogs is becoming available at an every increasing rate. Most of this work is focused on diseases that clearly have a genetic origin and as such are generally restricted to a few breeds (particular those which have been intensively selected and are inbreed).

 

Fortunately, greyhound (particularly racing greyhounds) is a very healthy breed. Much of this is the result of selection for fitness and concerns about excessive inbreeding. As far as I know, there are no research groups focusing on the greyhound, as the occurrence of known inheritable diseases is very rare. Having said that, the group that is most likely to be interested would be the Animal Genetics Laboratory within the Veterinary School at the University of California – Davis.

 

While the medical conditions your dogs suffers from clearly could have a genetic basis, it is also important that you confirm that these are not do to other more treatable causes. While others are possible, I would suggest you would want to be sure to rule out a mild or sub-clinical form of diabetes which would require special tests.

 

I think as more and more adopted greyhounds reach their senior years, the possibility exists that some inheritable diseases are not as rare as previously thought. It wasn't all that long ago that the majority of dogs did not make it far enough along in life to even identify that a disease existed.

 

Heather, I can tell you that Pam Davis (onrushpam) has taken a special interest in identifying which lines in greyhounds seem to inherit PRA (or maybe all related eyesight disorders) to share the information with other breeders and hopefully prevent more occurances of the disease.

 

For anyone whose dog has been diagnosed, I think she would like to hear from you and get your dog's racing name, DOB, sire, dam, etc.

 

Jenn

[Guest KennelMom]

Thanks Jenn....That's really interesting. I'll contact Pam with my pups info. I noticed she'd posted in an older thread about her cocker that had it.

 

 

 

Not to be argumentative, but why would (most) racing greyhound breeders care about things that would afflict the dogs post-retirement? Especially if the genes in question also carry favorable racing traits. I would imagine they wouldn't even know about it until years down the road if at all & in the case of a popular sire, long after the genes had been passed down.

 

Well, it seems that some dogs are affected as young as 18-24 months (just going by posts on GT)...so that would affect racing owners.

Edited January 22, 2008 by KennelMom

[jenn8]

Not to be argumentative, but why would (most) racing greyhound breeders care about things that would afflict the dogs post-retirement?

 

I am kinda thinking that the breeders and/or people they breed dogs for would prefer not to have their dogs face any type of health problems, before or after they retire.

 

Jenn

 

[Guest greytmonty]

It looks like a group at Cornell is studying this. DId you find this information?

 

cornell study on PRA and genetics

[sweetdogs]

Not to be argumentative, but why would (most) racing greyhound breeders care about things that would afflict the dogs post-retirement? Especially if the genes in question also carry favorable racing traits. I would imagine they wouldn't even know about it until years down the road if at all & in the case of a popular sire, long after the genes had been passed down.

 

Well, it seems that some dogs are affected as young as 18-24 months (just going by posts on GT)...so that would affect racing owners.

But would they attribute it to PRA? Would they take a young dog not racing as well as they think he should to an opthamologist for a diagnosis of a relatively rare, recessively carried disease? Or just have him grade off or never put him on the track at all? There are plenty of dogs that grade off at that age for a wide variety of reasons, some known, some not. And then go back through the pedigree & attempt to weed it out? Again, not trying to be negative because I'm sure some would & do go the extra mile. It just wouldn't seem to make economic sense for many.

[Sighthounds4me]

Not to be argumentative, but why would (most) racing greyhound breeders care about things that would afflict the dogs post-retirement?

 

I am kinda thinking that the breeders and/or people they breed dogs for would prefer not to have their dogs face any type of health problems, before or after they retire.

 

Jenn

 

Well, you would hope so. But my impression is, and has always been, that racing Greyhound breeders care primarily about money. Meaning that they are going to breed the best racers to the best racers, and hope to come up with even better racers. While they care about the puppies' health as it applies to this end, yes, they will breed healthy pups. But after they retire and are petted out, the breeders do not care, mainly because it's very difficult to keep up.

 

Having said that, I am sure there are plenty who do care. And I suspect as more and more adoption groups work to place Greyhounds as pets, even more racing breeders will start to realize that long-term health is important.

 

But it's still not like a reputable breeder of show stock, for example. Breeders like my boys' breeder, for example, breed rarely, and very responsibly. My boys are a part of their most recent litter, and will be 5 years old in March! So for them, it's far easier to keep up on health, because they own dogs from the litters they breed (for their whole natural lives), and keep in contact with buyers of the pups. They can follow the health of the parents, and grandparents, as well as following the health of each pup. It's harder for commercial breeders of racing Greys to do that, because they breed far more...

 

BUT, the good new sis, with the age of the internet, it's far more possible that sources such as Greytalk, and other databases may just make it easier to moniter long-term health of dogs bred by racing breeders.

[onrushpam]

I haven't looked at this much lately...

There are several types of PRA, and it varies by breed.

What's been seen in greyhounds is late onset PRA. It is recessive, meaning both sire and dam must be carriers to produce pups afflicted with PRA.

 

Yes, it is HUGE to know that Molotov was a carrier. He's been "doubled" a lot. So, yes, I think we can expect to see more of it in retired dogs.

 

The bad news is, PRA will rarely show itself while a dog is still running. It is much more typical for it to manifest in later years. So, racing breeders aren't likely to recognize it as a problem to be dealt with. They certainly won't eliminate Molotov offspring from their breeding programs!

 

The good news for adopters is that dogs with PRA adapt very well. It's often hard for the casual observer to know the dog is blind. One of my cockers completed her CDX obedience title, including jumping and retrieving, when she was almost totally blind. Her heeling suffered, because she glued her nose to the back of my leg. That's how we figured out she had a problem. But, as long as I was consistent, she knew how many strides to take before she jumped and she retrieved by sound/smell. She ran around the yard just as she always did. She knew where the trees were!

 

I'd be interested to hear about other Molotov offspring with PRA. Because he was so prolific, I'm surprised it hasn't become known before now.

 

I suspect PRA, like other diseases/syndromes, is only partially genetically linked... there may be genetic mutations happening that cause it to manifest. I heard an interesting piece on NPR yesterday about identical twins that have allowed scientists to narrow the causes of juvenille lukemia. One twin had lukemia and the other didn't. They have now identified a "pre-cancerous" cell that can lie dormant unless it is "activated" by a genentic mutation. One twin had the mutation, the other didn't.

 

I suspect something similar may be going on with PRA. Otherwise, we'd see a LOT more greyhounds afflicted with it.

 

Edited to add... YES to whomever mentioned the Ocuvite supplement. We used it with our cocker and felt it did make a difference!

 

Just my very unscientific .02...

Edited January 23, 2008 by onrushpam

[Brindles]

Julio has PRA. It started when he was 4, and fully set in at 9. His was a slow progression.

 

Not sure if it has been posted, but here's some news: According to my opthamologist, dogs with PRA don't go completely blind. Their field of vision goes from full down to about 2 degrees. Just that much makes things a lot easier for him.

 

It's hardly a handicap for Julio.

[Guest KipperGrey]

My Kipper(Able Ott) who passed this past June had PRA. He was almost totally blind by the time we caught it. He did see a Vet Opthomologist for the diagnosis. His daddy was Greys Statesman and mom was In a heartbeat. When we found out I did research and was also looking for anyone that would have wanted his info for genetic research information. His mom only had 2 litters...one with Greys Statesman and one with Molotov. I wonder how many of his siblings had PRA.

[Guest Redpack]

Yikes!

 

 

[NCGreyhounds]

My Kipper(Able Ott) who passed this past June had PRA. He was almost totally blind by the time we caught it. He did see a Vet Opthomologist for the diagnosis. His daddy was Greys Statesman and mom was In a heartbeat. When we found out I did research and was also looking for anyone that would have wanted his info for genetic research information. His mom only had 2 litters...one with Greys Statesman and one with Molotov. I wonder how many of his siblings had PRA.

 

Our newest adoption, Iruska Creme Pie (now "Hottie") appeared blind last night - first we ever noticed it, but last night, it was dramatic. In looking up "night blindness" everything seems to point to PRA so I'm reading all the posts on GT about it. She has an appointment on Tuesday and I can't help crossing my fingers that it's something else- something curable.

 

Responding to your post because Hottie is the daughter of my all-time heart dog, Iruska Zinnia who passed last summer - her sire was Greys Statesman. Zinnia had 43 offspring before we were allowed to adopt her, and Hottie had two litters of her own.

 

I am so worried... we had a blind greyhound years ago who did just fine. It's just not something one wants to anticipate...

 

Cara

[tbhounds]

If you suspect PRA I would not wait until Tuesday to have your hound checked.

[Guest sja5032]

If you suspect PRA I would not wait until Tuesday to have your hound checked.

 

Why? I am not an expert by any means but from what others have said I have gathered that there is no cure and its not very fast acting. Just curious as to why you would rush to the vet?

[Guest KennelMom]

If it is PRA, there's really no need to rush to the vet. There's nothing you can do about it, though there are a couple supplements/protocols that might help slow the progression. A couple days won't make a difference. However, if it were a sudden onset of blindness or something else causing vision problems, quicker intervention might make a difference. You'll probably end up at an opthamologist anyway, which can take a little time to get into, depending on where you live. One of the first things we noticed in Hanna wasn't even difficulty seeing or night blindness, it was that her eyes were staying dilated in the bright sunlight. That's actually what got us into the vet initially.

 

fingers crossed that Hottie can make a full recovery Keep us posted! Fortunately, PRA is still very, very rare in greyhounds.

[krissy]

In a thread I had started a few months back about Summit's pannus diagnosis someone (sorry, I forget who it was) mentioned I should be double sure we checked his retinas really well for signs of PRA because Summit's grandsire was Greys Statesman who is a carrier. In this thread I see all the talk is about Molotov, and honestly I only know what I remember being told so I'm not sure if GS is a carrier or not, but just thought I'd throw it out there.

 

Summit was cleared as just having pannus. He has some iris atrophy. No retinal atrophy (right now, fingers crossed it stays that way). He is Jimbo Scotty X AMF Curveball for anyone's interest.