I've been reading this really interesting book called The Dog and it's Genome. One of the chapters is about how breed clubs have dealt with genetic disorders. They tell this story about the Portugese Water Dog in the US, which had a problem in the late '80s with a genetic disorder - with about 1/3 of dogs as carriers. A blood test was developed that allowed them to id carriers. The club, on good advice, recommended that breeders use a breed and replace approach - that they breed their good quality carriers to non-carriers and keep non-carrier progeny to replace the carrier parent while retaining their genes. But most breeders made what they no doubt felt was a morally correct decision and chose not to breed their carriers at all. Which reduced the gene pool markedly.

It was realised that this particular disorder came from one of the two main counrty of origin families in the breed, so breeders swung mainly to using the other line. But within a short period of time they realised that this family carried a kind of PRA - and that this occurred at a higher rate than the original condition.

They also talked about a family of Dalmations that were developed from Dal x Pointers to eliminate the kidney stone problem that Dals have (apparantly all Dals are homozygous for the gene that causes the purine absorbtion abnormality) - but after many generations (they started in the late 70s - the percentage of pointer DNA must be so tiny at this point) they haven't been able to get the big, round Dally spots - which suggests that the gene that causes the abnormality and the proper Dal spots are related.

yes that is very interesting and very good to keep in mind i think i would have been an odd one out if i was breeding the portugese and would have tried to keep the old good carriers going by breeding them to them non carriers but then i would have hit the same problem as i think many of the breeders did and no one would have brought any of my pups and that is why it probaly happened the way it did and the same with the dali's

What they were advised to do was place carrier pups as d/s pets. So that they were carriers should have been irrelevant. But just goes to show you can make mistakes precisely because you try to do the right thing.

In another chapter about this project in PWD... http://georgieproject.com/
they identified that there were multiple genes/gene-complexes causing hip laxity (not sure if that means will definately get HD, or just a risk factor)and - and this is what I find interesting - the dogs with the best hips had1 each of 2 different genes that, if they had 2 of them, would cause bad hips - so that if you bred the dogs with the best hips to each other you'd still produce pups with bad hips.

yes well that sucks lol SORRY! very tired this morning i have had a dam tom cat hanging around very night for the last week i don't know were it has come from but i know were it can GO he has been singing under my bedroom window and sounds like he is about 1000 years old, my cat has been de-sex for 8 years and as my dogs have never been aloud to chase cats so they are useless at getting rid of him.
buy the way kooliemum are you coming up to our workshop would love to meet you then we can really pick our dogs to bits lol won't be a gene left on them

I wasn't planning to - it would mean I have to take time off work. What are the dates?

26th and 27th Anzac weekend