The Role of Canine Health Databases

I agree with you about having a health requirement for an ROM but would also like to see some type of award from BHCA for all genetic testing done of any basset or at least those who achieve championship status.

In 1983, on behalf of the Basset Hound Club of Southern California, I made a proposal to the BHCA board that a health registry be established for thrombopathia. It did not happen. We were experiencing a lot of thrombopathia in So. Calif. at that time -- about 35% of the 35 or so dogs tested at UCI over about a year were either affected or carriers. I still feel that a club registry would be worthwhile, but should not be limited to thrombopathia exclusively.

I certainly agree with your statement, "It would be nice if a "thrombopathia normal" or a "OFA hips-excellent" had the same importance or prestige as an AKC or BHCA title."

Our philosophy is that there are three aspects to the well balanced basset -- conformation, temperament and health, nothing less.

In the last conversation I had with the director of OFA I was told that there were less than 100 bassets in the OFA data base. It is interesting to do a search on kennel names in that data base and find how many are absent. It's difficult to get a basset to pass OFA but that doesn't mean we shouldn't keep trying. If we take the best we've got and breed to the best we can find we will improve.

If anyone is interested I've tried to compile a list of the diseases and disorders that are listed as genetic or thought to be hereditary by George Padgett in our breed. You can find them on our kennel webpage Many of these links are thanks to Betsy's research of health sites out there. I personally think we should have an award for Betsy's contribution to the education of breeders.

And by the way, Ray and I took 5 bassets to Cornell in June for thrombopathia testing. That's 6000 miles round trip. We haven't tested in a number of generations and have done outcrosses in the meantime. We were pleased that all were normal.

The committee presented it to the Board last year, and our proposed clearances are gonioscopy, vWF and thyroid. There are standardization problems with gonioscopy reporting that I mentioned earlier, and CHIC has asked us (BHCA) to work with ACVO to see whether some sort of standardized reporting of gonioscopy results can be developed.

CHIC is also reluctant to use vWF ELISA results. It would therefore be helpful to have a DNA test validated or developed for Bassets. Unfortunately, our call for specimens for VetGen has, so far, generated a rather poor response.

I would have liked to have proposed thrombopathia testing as a clearance, but because this testing isn't as widely available as the others, there was concern that its inclusion would further limit registrations. If Dr. Boudreaux is successful in developing a DNA test, then we'd move to include it.

So, to answer your question, BHCA is exploring the feasibility of joining CHIC, but we've still got a some issues to smooth out.

Also--Dr. Padgett, mentioned in the above links, is speaking at Nationals on Saturday afternoon.

The ophthalmologist I use in Portland feels that gonioscopy is useless in predicting glaucoma. I suspect he's not alone in his beliefs. When I test I feel like I'm just going through the motions.

A DNA test for vWD would be wonderful, but the ELISA assays are still very useful if done by the right lab. You should talk to Jim Catalfamo at Cornell and have him explain to you what has happened to the test that he and his colleagues developed, and why results are not always good. I nearly eliminated our best producing bitch from our breeding program because she had very low vWF results when test locally. I was devastated, but I decided to take her along when we took all the others to Cornell in June, and guess what? She was well within the normal range, even though she was in a false pregnancy.

Just because thrombopathia testing isn't widely available doesn't mean it couldn't be included.

Your quote: "So, to answer your question, BHCA is exploring the feasibility of joining CHIC, but we've still got a some issues to smooth out."

Sorry Betsy, this is the same kind of line I've heard for 25 years. Testing will never be foolproof and there will always be those for whom it isn't available. We can't use that as an excuse for sitting back and doing nothing. Think where human health would be if we sat back and waited until all tests were perfect and all treatment could guarantee no side effects.

And why is hip dysplasia ignored. That's easily identifiable and it's a definite problem in this breed.

Regarding Dr. Padgett, I'll be harvesting chestnuts this year the first week of October. Is there any possibility of videotaping his presentation? If anyone is doing it I'd be glad to pay for a tape. It would make a great presentation for our club. We heard him at Michigan years ago and he's outstanding.

Gonioscopy--Although we don't have recent basset-specific data, there's evidence in other breeds (Flat Coats, Great Danes) that goniodysgenesis is significantly associated in affected dogs with the development of glaucoma, goniodysgenesis is heritable, and that breeding dogs with no or minimal goniodysgenesis decreases the incidence of glaucoma within a breed.

The study below (Great Danes) indicates that if both parents have no more than minimal goniodysgenesis, then glaucoma would affect their offspring at a rate of < 4/1000.

Link: http://www.electronicipc.com/JournalEZ/det...=04290010620928

Am J Vet Res 2001 Sep;62(9):1493-9

Relationship of the degree of goniodysgenesis and other ocular measurements to glaucoma in Great Danes.

Wood JL, Lakhani KH, Mason IK, Barnett KC.
Epidemiology Unit, Animal Health Trust, Newmarket, Suffolk, UK.

OBJECTIVES: To assess the association between goniodysgenesis, ocular measurements, and glaucoma in Great Danes. ANIMALS: 180 Great Danes. PROCEDURE: Eye examination and measurements were obtained from 180 Great Danes; for 30 of these dogs, depth of the anterior chamber, vitreal body length, and total depth of the globe were also measured. These data were merged with electronic pedigree information on 43,371 kennel club registered Great Danes. Relationships among goniodysgenesis, ocular measurements, and glaucoma and the heritability of goniodysgenesis were estimated. RESULTS: The degree of goniodysgenesis was significantly and positively associated with the likelihood of glaucoma. There was a significant association between the degree of goniodysgenesis in offspring and parents. The estimated heritability of the degree of goniodysgenesis was 0.52. The depth of the anterior chamber of the eye was also a good predictor of goniodysgenesis (ie, the dog was almost certain to have glaucoma if the depth was < 3.7 mm). If both parents had goniodysgenesis < 70%, then with 95% confidence, the occurrence of glaucoma in the ensuing offspring would be < 4/1000. This strategy translates to ensuring that the depth of the anterior chamber of the eye is > 3.7 mm for both parents. CONCLUSIONS AND CLINICAL RELEVANCE: The strong and significant correlation among goniodysgenesis, other eye measurements, and glaucoma and the significant heritability of goniodysgenesis suggests that glaucoma may be heritable in Great Danes. If so, glaucoma can be controlled by breeding only from sires and dams with a minimum degree of goniodysgenesis.

PMID: 11560283 [PubMed - indexed for MEDLINE]

Discussion of the significance of goniodysgenesis in Flat Coats can be found here. The following is an exerpt from this webpage.

     

Detailed studies have been carried out of the disease in the UK population of flatcoats, involving diplomate clinicians, as well as epidemiologists  and statisticians. These studies have now been published in the scientific journal Veterinary Ophthalmology (Vol 1, pp85-90, 91-99). These studies have enabled several important facts about the disease in          flatcoats to be properly established.

The data demonstrated a close relationship between the degree of goniodysgenesis (or PLD) and the likelihood of an animal developing glaucoma. Animals that are only very slightly affected (or are clear) are unlikely to get glaucoma and as the proportion of the eye that is affected increases,          then so does the risk.

Overall, there was no indication of a substantial worsening of the condition with age and so an animal, which is screened clear at a young age, is unlikely to develop the disease later in life. Thus, animals can be screened as young adults and the likelihood of them developing glaucoma can be accurately assessed (as well as their suitability for breeding, see below).        

The degree of goniodysgenesis (or PLD) was highly heritable (h2>0.7), indicating that if one bred from animals with no, or only very limited goniodysgenesis, then the offspring would be most unlikely to suffer from glaucoma. Although glaucoma itself was not shown to be inherited, the close association between the predisposing condition (goniodysgenesis)  and the disease and the high heritability of goniodysgenesis can be taken to indicate that glaucoma is inherited. This is the first time that the heritability of this disease has been demonstrated scientifically in dogs.

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[ September 18, 2003, 09:45 PM: Message edited by: Betsy Iole ]