Critical understanding of genetic tests

[sandgrubber]

I haven't bred a litter for more than a decade now.  I ended up in a discussion about genetic testing and was a bit shocked to find that a big panel of tests, mostly for diseases I have never heard of, is now available for Labs (and most other common breeds). On checking a few out, I find, for example, that narcolepsy affects one in a million (and the affected are much sought after by medical research and may live long, near normal lives) and the 'hip laxity' tests are for one of many factors that may, in combination, cause hip laxity. I can only image the headaches involved in showing the results of such tests to puppy buyers, not to mention the minefield they open up when deciding whether to breed a bitch and what dog to use. 

Question: Has anyone found a good resource that details such things as the incident rate, range of severity, and age of onset for the conditions the tests represent?  Something NOT produced by the testing laboratories would be best.  They have a $ interest in convincing us the tests are needed and good. 

Also, some assessment of the accuracy of the tests would be handy. I once had a run in with a color test that, after the whelping, was obviously incorrect.  If 1/1000 dogs  carry some condition and the accuracy is 99%, most of the positive results are likely to be testing errors. 

[Rebanne]

I will be interested to see if you find something sandgrubber. Two of my greyhounds are supposed to be carriers of black skin disease but I have never heard of a Grey with it only toy dogs. Also when Opal was so sick last year and there was one disease mentioned and when I contacted the testing lab, they said they did not have a test for Greyhounds but could use another sighthound test on her ( from memory I think it was Borzoi but not 100% on that ).

 

I think, if they have a test available, then it is used on most breeds whether they have ever had a case of it or not. One of the colour tests for Greyhound was brown, they don't come in brown.

[Dogsfevr]

2 hours ago, Rebanne said:

I will be interested to see if you find something sandgrubber. Two of my greyhounds are supposed to be carriers of black skin disease but I have never heard of a Grey with it only toy dogs. Also when Opal was so sick last year and there was one disease mentioned and when I contacted the testing lab, they said they did not have a test for Greyhounds but could use another sighthound test on her ( from memory I think it was Borzoi but not 100% on that ).

 

I think, if they have a test available, then it is used on most breeds whether they have ever had a case of it or not. One of the colour tests for Greyhound was brown, they don't come in brown.

Black Skin is sometimes considered an issue with thyroid dogs .

Given Greys can have thyroid issues it’s come from there.

 

It May also not be related 

[Diva]

Not aware of any comprehensive listing as you describe unfortunately. The info is  probably in journals and text books but it’s a task if you are looking at a lot of conditions. 

 

I’ve long thought we need clinical geneticists advising breeders in the canine world as there are for people dealing with human DNA test results.

 

We have molecular geneticists and population genetics but there is a gap in professional advice on how to interpret and use testing results in a measured way in breed decision making.

 

My breed has only one applicable DNA health test, for the SOD1 degenerative myelopathy mutation, so I just do that and don’t bother with DNA panels, except for colour which I do out of interest. It’s a simple autosomal recessive, 2 copies put the dog at risk of the disease in old age rather than definitely getting it, so in a pretty healthy breed with average genetic diversity it’s not hard to manage. But I feel for the juggling act many breeders must face. I have been playing around with haplotype and genetic diversity testing but even with a science background it’s hard to knit it all together, too many unknowns and too much rhetoric.