Genetic Testing .. not understanding is the problem - Page 1

http://www.scientificamerican.com/article/puppy-bred-to-have-muscular-dystrophy-saved-by-surprise-mutation/?ref=yfp

An interesting story about using a single marker to attempt to breed out a disease in Golden Retrivers.  Turns out that using this test was also breeding out a useful mutation against the same disease and potentially other diseases.  The existing mutation was called a "surprise" but in fact was an existing mutation that was unknown.  Not knowing something and making discoveries is not a surprise in science .. it is normal.  The story points out the dark side of genetic screening for diseases based on imperfect testing methods and poorly understood science.  Some genetic tests can quite literally throw out the baby with the bath water.

http://www.bizjournals.com/prnewswire/press_releases/2015/11/12/DC56257

The Jagged1 mutation and effects are well known in humans .. it just wasn't known in dogs and is likely present in other breeds as well.

Interesting.  Our UK Royal Veterinary College has a programme of
breeding Beagles with Muscular Dystrophy, in particular the Duchenne
type of the illness, trying to find new treatments ;  this project began a
few years ago when vets discovered a whole family of cross-bred dogs
[Cavalier King Charles Spaniel X Bichon Frise] which were dystrophic.

Dogs from this family were bred with Beagles (which were chosen due to

less genetic problems than other breeds, making results easier to interpret).

Strands of DNA will be added to dystrophic dogs, to restore the disrupted

'messages' to their protein making cells and allow them to start making

dystrophin again.
Actual testing starts in 2016.
www.theguardian.com/science/2015/nov/15/beagles-study-hope-cure-
muscular-dystrophy.

Not a surprise to me. A good example from human genetics is the sickle cell gene. In its heterozygous form, it protects against malaria, which explains why the gene is most common in Africans from areas where malaria is endemic.

the problem is when they mix with the population,always life finds a way

Regardless of movie quotes .. genetic research and science at this point has lots of data and very little understanding of most of it. At this point science can sequence an entire genome but understands 1% of the results.

This is why genetic testing is still very much "customer driven." Many breeders have accepted the use of hip/elbow x-rays but the other tests are still not that widely accepted due to their lack of accuracy. Even hip scores to an extent are still questionable as to how they affect the next generation but because it has shown to have a positive affect since it's inception, reputable breeders are basically required to do that test. The newer tests are really just a selling point to a portion of the population that "thinks" they've done research and need the sire and dam of their puppy tested for everything possible.

Breeding needs to be a balance, you need to weigh the good and the bad. When you put too much weight on a single genetic marker and forget about the rest of the picture, you're bound to fail. Unfortunately, there are breeders that are succumbing to the market pressure and weighing the uneducated customer demands for genetic testing higher than producing solid all-around dogs.

Agree totally, BW. Your last paragraph especially.

Not testing for mad cow, scurvy, and preeclampsia makes you a bad breeder against the BYB next door who has poor quality dogs who have never been tested for what's important (temperament, drive, OVERALL health and vigor) but has tested for every disease known to man.